Can an observer prove that a given public key is the n^th hardened child of a given xpub without access to any of the associated private keys if they know n?

Alternately, can the owner of the private keys create such a proof?

[do]

https://github.com/bitcoin/bips/pull/159

Payment codes are a technique for creating permanent Bitcoin addresses that can be reused and publicly associated with a real-life identity without creating a loss of financial privacy.

They are similar to stealth addresses, but involve a different set of trade-offs and features that may make them more practical.

You can publicize your payment code in the same way that you can publicize your email address. Even if everyone knows your payment code, nobody can monitor the blockchain to see how many payments you have received or which transactions are yours.

If you receive an incoming transaction to your payment code, the act of learning that you received funds tells you the payment code of the person who sent the transaction. This means transactions sent to payment codes do have the "from address" that's missing from Bitcoin wallets and that many users would like to have.

Since transactions involving payment codes have a from address, the recipient of a payment can send a refund to the sender without requiring additional information.

Unlike stealth addresses, detecting incoming payments does not require scanning the entire blockchain and all transactions. Any method used by light clients to obtain their balance normally also works with payment codes. This means a light client can use payment codes without outsourcing their privacy to a trusted full node.

Payment codes have different privacy features than stealth addresses:

• Payments sent to a stealth address are obviously identifiable to network and blockchain observers as sends to a stealth address and could conceivably be censored. Payments sent to a payment code are not distinguishable from traditional Bitcoin transactions
• Payment codes leak an upper bound on the number of incoming notification transactions a known payment code has received. The senders of those payment codes, whether not a particular notification transaction is a valid payment code or not is not leaked. Notification transactions are identifiable by a network or blockchain observer and could conceivably be censored.
• Stealth address transactions put the information that's contained inside a payment code notification in every transaction. Payment code notification transactions include an extended public key that only needs to be sent once to each recipient and is which is valid for 2³² subsequent payments.

The payment code standard does not currently support multisig payment codes, and there's no obvious way to add support for them without either losing desirable features or failing to provide the additional security that multisig addresses are supposed to provide. It might be possible to use threshold signature techniques to accomplish the goal of allowing multiple parties to share control over a payment code without requiring OP_CHECKMULTISIG scripts. This will be a subject for future investigation.

The full description of the protocol with illustrations is available here:

https://github.com/OpenBitcoinPrivacyProject/bips/blob/master/bip-0047.mediawiki

This project does not yet protect against BadUSB style exploits, however their approach might be capable of being extended to doing so.

This weekly meetup wil feature a presentation by Michael Goldstein where he discusses is recent article, "Everyone's a Scammer"

RSVP for the in-person event here: http://www.meetup.com/BitcoinAustin/events/208551212/
Watch live here:  https://plus.google.com/events/ct8mk22fi43e0lknjoolrgv56ok
View the recording here: http://www.youtube.com/watch?v=XfsK3EYrgLg

http://www.reddit.com/r/Bitcoin/comments/2exd3e/bitcoin_btcd_and_golang/

This is a video from a combined event between the Austin Bitcoin Meetup and Austin Go Language User Group.

There are three parts:

Part 1 is an introduction to Bitcoin by Marco Peereboom, and probably doesn't offer much to readers of this subreddit.

Part 2 explains the business reasons why Conformal decided to switch from C to Go.

Part 3 is Dave Collins's presentation on btcd's architecture and use of Golang features.

Part 3 is notable in that Dave decribes the weaknesses of Go in addition to its strengths, and how they mitigate them.

PDF copies of the presentations are available here:

https://github.com/ATXBTC/Presentations

PS: The Austin Bitcoin Meetup will be conducting similar events with the local Python, Javascript, C, Java, etc user groups. If you're a developer of a relevant project and would like to participate, contact us.

If I recall correctly, Atlas was banned for faking suicidality on the forum. So I think there should at least be a standard of not allowing threats like this in threads:

arepo already killed himself back in May, and there will be a lot more suicides coming

There isn't much in the way of a standard for decorum here, but I'd like to suggest that comments like the above, at a minimum, are off topic.

Note I've been reporting such posts and I'm creating this thread to get some feedback so that I know if there's any consensus or if I'm wasting my time.

http://www.meetup.com/BitcoinAustin/events/200977752/

When: 2014-08-27, 7:00 pm
Where: Brave New Books, Austin, Texas, USA
What: Dave Collins and Marco Peereboom will join us to explain Btcd, an open source implementation of the Bitcoin protocol written in Go.

Developing cryptocurrencies is an exciting endeavor that touches a wide variety of areas such as wire protocols, peer-to-peer networking, databases, cryptography, language interpretation (transaction scripts), RPC, websockets, and QA.

Dave and Marco will describe how they approached these areas from a Go perspective and their future plans and roadmap for the project.

This is a joint event between the Austin Bitcoin meetup and Austin Go Language User Group.

Refreshments will be provided courtesy of Umbel.

[Status]

This thread is to track the progress of stealth address support in various Bitcoin clients.

In order for stealth addresses to be useful, it's necessary for Bitcoin clients to support sending funds to them, even if those clients do not support receiving funds via a stealth address.

To accelerate this process, anyone who would like to see stealth addresses become a standard feature of the Bitcoin landscape should ask the developers of their wallets they use to support at least sending to stealth addresses. Since in some cases the developers may be reluctant to add this feature and may be unwilling (or unable) to explain why, asking them in a public forum is best so that their answer - or refusal to answer - is also public.

Please feel free to create feature requests, etc for clients that aren't in this list and link them in this thread so I can add them to this post.

sx
Status: supports sending and receiving

http://sx.dyne.org/stealth.html

Dark Wallet
Status: supports sending and receiving

https://wiki.unsystem.net/en/index.php/DarkWallet/Stealth

Electrum
Status: Sending support:: https://github.com/spesmilo/electrum/pull/817

Bitcore
Status: Sending support: https://twitter.com/ryanxcharles/status/514224778052243456

https://gist.github.com/ryanxcharles/1c0f95d0892b4a92d70a
https://github.com/ryanxcharles/bitcore2/blob/master/lib/expmt/stealthmessage.js
https://github.com/ryanxcharles/bitcore2/blob/master/lib/expmt/stealthaddress.js

btcwallet
Status: interested, no immediate plans: https://github.com/conformal/btcwallet/issues/90

airBitz
Status: "very interested", no immediate plans https://twitter.com/anonymouscoin/status/496513836133154816

Mycelium
Status: Tentatively interested: https://twitter.com/MyceliumCom/status/500327004022243328

Coinkite
Status: "at some point": https://twitter.com/Coinkite/status/509489249826373632

Armory
Status: no official comment: https://github.com/etotheipi/BitcoinArmory/issues/226

Blockchain
Status: unknown

Bitcoin-Qt
Status: unknown

Multibit
Status: unknown

Coinbase
Status: unknown

[Bitcoin and the Agency Problem]

http://nakamotoinstitute.org/mempool/bitcoins-rugged-individualism/

Bitcoin and the Agency Problem

Whereas for earlier moneys, it was generally the case that most people could expect to be better off storing the bulk of their money with agents, for Bitcoin the opposite is true. The Bitcoin network obviates traditional financial institutions and there are really only two agents that Bitcoin users need: exchanges and payment processors. The exchanges are temporary; they are only required because fiat currencies require them. Once the fiat currencies have died, centralized currency exchanges will no longer be required. As for payment processors, they are only required over time scales of about an hour or less to ensure that a transaction gets into the block chain. With Bitcoin there is no need for anything like a bank that would store bitcoins over a long term.

Being nearly superfluous is not the only problem with Bitcoin agents. To whomsoever a private key to a Bitcoin address is known, the bitcoins it holds are far easier to control than dollars or gold are under almost any circumstance. This is because controling bitcoins is simply a matter of keeping a number secret and requires neither securing physical matter (as with gold) or the permission of issuers (as with dollars). Thus there is a fundamental agency problem with Bitcoin. Agents can disappear or simulate a heist upon themselves. They cannot rationally be trusted without extreme costs being imposed on them which are more stringent than traditional banks. Furthermore, agents must advertise their services and consequently become the targets of hackers. They must take extreme measures to achieve a level of security similar to that which an individual person achieves with much less.

The inherent agency problem in Bitcoin is borne out by Bitcoin's extraordinary history of hacks and thefts. Bitcoin institutions seem to be worse than the banks that Bitcoin replaces. As Bitcoin proponents must point out repeatedly to naysayers, people lose bitcoins not by an inherent flaw in the protocol, but by misuse. They stored them with Mt. Gox, Atlantis Market, or one of many other companies that imploded or disappeared. Bitcoin has had a problem with amateurish entrepreneurs, but I expect that we will see continued failures even when established institutions attempt to use Bitcoin.

Despite this, there are still a lot of Bitcoin agents. The practice of storing bitcoins in web wallets, like those provided by CoinBase and Circle, abounds. People are still used to dealing with banks as a necessary evil and are not yet comfortable with the skills required to safeguard a private key. This is a problem because it means Bitcoin adoption requires a real change in peoples' habits. Everything that helps people to learn new habits is greatly appreciated.

The only solutions to the agency problem are either to remove agents or to remove their agency. In other words, people must either take control of their own bitcoins or, if they do not wish to, they must cede control of their bitcoins in a way that does not give control to an agent. The only way to do this is to spread the control over many different parties who are not expected to collude. This could be done with multisig wallets or Open Transaction voting pools. This is a fairly drastic solution because it means no one can do anything with the bitcoins on his agency alone.

Bitcoin Institutions

The agency problem becomes especially interesting when it comes to Bitcoin organizations because an organization has no autonomy of its own and all its members act as agents to it. All, whether employees or owners, have a similar incentive and ability to steal that other Bitcoin agents have. This is not a new problem, but Bitcoin gives it a new character.

An organization inherently cannot take control of its own bitcoins, so its only solution is to remove the agency of its own employees and owners. It is not enough for an organization to distribute keys between its own people, although that will help. However, it is much easier for people within an organization to collude than without, and furthermore within an organization people will tend to have similar characters so the probabilities that each is a bad actor are not independent of one another. Votes must come from different organizations on order to maximize the security of the wallet.

Criminal Organizations

Whereas individuals can do whatever they want with their bitcoins, organizations must seek outside approval. They must subject themselves to constant auditing in order to deserve any measure of trust. It has long been understood that Bitcoin gives more control to individuals, but the complement to that is not yet well enough understood. I believe history has shown it to be an important effect, but it is not yet clear how important it will be. Maybe people will be able to work around it or maybe they will have to replace most organizations with distributed systems.

Of course, the requirement of being constantly audited and losing control over the funds it holds is less of a problem for honest organizations. It is much worse for criminal organizations or for organizations that want to keep their internal operations secret. Mafias, cults, and governments will have a greater difficulty adapting to Bitcoin than will publicly-traded companies.

All organizations tend to evolve so as to resist change, but governments, being subject to the problems of socialism, suffer much worse from this because government operations lack a clear concept of efficiency their overall success, the relative importance of any of its parts, or the relative merits of alternative organizational structuring. Consequently, governments can more easily evolve into labyrinthian structures that nobody understands without anyone realizing what is happening.

An eye-opening article called Sinkhole of Bureaucracy describes a surreal example of this phenomenon in an outstandingly incisive way. In an abandoned Pennsylvania mine, which is now an office containing 600 federal employees and endless filing cabinets, process all the federal retirement pensions on paper by hand. The system is widely understood to be insane and dysfunctional, but despite repeated and ceaseless attempts to automate the process beginning in the early 80's, the system has not changed. It is not a problem of will, but of knowledge: there is no one available with the skills to carry through the transition successfully, no one who knows precisely what those skills would be, and no one who can evaluate anyone else for them. As a result, the attempts to develop an automated process failed because the software engineers did not understand the laws and the bureaucracy well enough to design something correctly, and the bureaucrats did not know how to tell if the software engineers knew what they were doing.

Will the federal government be able to adapt to Bitcoin? This would require building an a system not just for the one department, but for the entire organization, and it would have to be built properly—it must distribute decisions enough so that bitcoins cannot be stolen easily by employees. After reading that article, I think it is reasonable to think that the government may not be up to such a task at all.

http://www.youtube.com/watch?v=mu1iND6vtcE

http://www.meetup.com/BitcoinAustin/events/188380302/

When: Sunday, June 15, 2014 7:00 PM to 10:00 PM
Where:  Brave New Bookstore 1904 Guadalupe St, Suite B (Downstairs), Austin, TX


This week we'll be joined remotely by Kristov Atlas for a Q&A session.

Kristov is the author of Anonymous Bitcoin, host of Dark News, and recently discovered a privacy flaw in the Shared Coin service of blockchain.info

Executive Summary:

The SharedCoin mixing service provided by Blockchain.info offers only limited privacy to users due to weaknesses in its design. Bitcoin users should carefully consider their privacy requirements and evaluate other mixing services if they require serious privacy guarantees. A tool for analyzing SharedCoin and other CoinJoin-based mixing protocols will be released approximately two weeks following this advisory to allow SharedCoin users adequate time to protect their privacy.

http://www.coinjoinsudoku.com/advisory/

If someone was designing new forum software from scratch, one of the things they should do is rethink categorization of posts.

Clearly, many users don't know or are not willing to post topics in the correct section of the forum. This can be caused by simple ignorance or malice. Either way, it greatly distracts from the usability of the forum and sucks up moderator time and attention.

Letting posters the category first and them cleaning up after them later is suboptimal, so why not reverse the process?

A user composes an new thread, but does not get to choose the category up front. When they are ready to submit their post, the forum chooses the category for them by having the poster interact with a finite state machine via a series of questions similar to the following:

1. This post is written in:

• English
• Español
• 中文

2. The primary topic of this post is:

• The Bitcoin network, software, or currency
• A different cryptocurrency
• Something else

The FSM end state is the section where the thread is posted.

Optionally, the forum software could do simple text analysis of the post and thread title to find possible duplicate threads, and ask the user to affirm their thread is new and not a dup.

Lying during the submission process in order to deliberately miscategorize a thread is a bannable offense.

The forum tracks member status (brand new, newbie, full member, hero member, etc) on a per-section basis taking into account how many of their threads get moved to other sections. If a user maintains a sufficiently high accuracy rating they "unlock" that section and can post to it directly without going through the FSM.

This would be a lot of work to implement up front, but I suspect it would greatly reduce the ongoing moderation burden, especially because it removes most or all plausible deniability for trolls.

http://themisescircle.org/blog/2014/02/25/bitcoin-has-no-image-problem/

Why Doesn’t Bitcoin’s Success Speak For Itself?

Bitcoin has an image problem! Everyone thinks Bitcoin is for drug dealers, hackers, and anarchists. It’s used to gamble and buy porn. People think it’s a Ponzi scheme! Bitcoin needs to grow up and repudiate its youthful indiscretions. Its services must be run by professionals, not amateurs!₁ Soccer moms will never use Bitcoin if they think it’s used for drugs and porn. Bitcoin will never be acceptable and gain widespread adoption otherwise!

In this article, I will show why the above paragraph is totally misguided.

Bitcoin is far too useful to expect that prejudice will stand in its way. Almost everyone who has ever bought bitcoins had to overcome an initial skepticism, and this will continue to be the case right until Bitcoin takes over. To want bitcoins requires a person who can see ahead a little bit better than everyone else. The only way to convince most of them that Bitcoin is in their future is to build that future and show it to them. Those with a less entrepreneurial mindset will simply have to be in much worse financial straights without it before they will be ready to adopt.

The data on Bitcoin’s adoption rate show no evidence of an image problem. First look at this log chart of Bitcoin’s market cap.


_{Bitcoin’s image is so bad that it’s been growing exponentially since its inception.}

Now take a look at the number of MyWallet users over the past two years. This is also a log chart.


_{That’s an increase of like 500 times in two years. Ooo, I’m so terrified Bitcoin’s image will stop people from wanting it.}

And what about BitPay, Bitcoin’s premier payment processor? In September of 2013, they signed up their 10,000th merchant. By December, they had over 14,000. On Black Friday of 2012, they processed 99 payments. That same day of 2013, they processed 6,296.

Are you kidding me? I’ve never seen anyone want anything this badly. People can’t get enough bitcoins. Every indication of Bitcoin’s adoption shows a rapid exponential growth. The idea that Bitcoin has an image problem is empirically ridiculous.

You could run an ad campaign for Bitcoin that tells people it’s the stupidest idea ever and punch people in the face when they bought in and they would still flock to Bitcoin. You know how I know that? Because that’s basically what has been happening since the beginning of the Bitcoin economy. N00bs enter the bitcoin world to find scams and sophmoric retards that give them terrible advice. They lose their investment from simple mistakes and they get raped by the markets. These are serious problems that need to be ameliorated, but the point is that Bitcoin can beat the shit out of people and they sill want it. This is how we know we don’t have to worry about Bitcoin’s image.

Bitcoin’s Image is Actually Great

I think Bitcoin has a great image and that Bitcoin’s association with illicit activity should not be seen as a problem for it. I can’t think of any better way to generate interest in Bitcoin than drug-dealing, hackers, and anarchy. When was the last time you heard someone say, “Oh, Bitcoin! I’ve heard of that. That’s that new currency that’s great for remittances, right?” Never, that’s when. Drug dealing, hackers, and anarchy are great lead-ins to a conversation.

I remember the days when Bitcoin was so unknown that I was not even recognized as a dork for talking about them. In those days, nobody wanted to hear about Bitcoin, not even libertarians. If I tried to talk about them, it was like people didn’t even hear me. Now everyone wants to hear about it and I wouldn’t have it another way.

Furthermore, Bitcoin’s improvements to the illegal drug industry and to practical anarchism have been one of its greatest successes, so why shouldn’t people associate Bitcoin with drug dealers and anarchists? Not only is that just honest, but it is a very strong endorsement. If Bitcoin is good for illicit activity, that means it empowers people. If people think that Bitcoin can help them to evade contraband laws, to taste the forbidden fruit, to satisfy needs that society would rather have them suppress, then that is a fantastic advertisement.

Bitcoin is subversive as more than just a payment-processing technology. It is not just a cool new gadget that ordinary people can use without fearing that it will lead them unexpected new directions that test their ability to grow as a person. It has the potential to change their lives irrevocably. It has the potential to drastically change the balance of power in society. It is perfectly reasonable for people to be suspicious. People should feel a real twinge of danger when they first get bitcoins. It can usher them into realms which their society has long told them were off-limits. If we got people to believe that Bitcoin was only good for revolutionizing e-commerce, then Bitcoin would have an image problem because that would not be honest.

The Disconnect

These “image problem” people are like if the Clampetts discovered that they were sitting on a swamp made out of crude oil and worrying that people won’t accept it because it’s too ugly and gross, so they try to convince people that it’s a pretty shiny pink and tastes like cherries.
narcissism


_{Oh Narcissus, you’ll never understand Bitcoin.}

The only way to think Bitcoin has a bad image is by marketing it to the wrong people. Yes, just about everyone could benefit from Bitcoin right now, but for most people, the immediate benefit would be relatively small, and it is too much to ask them to understand both the economics and the cryptography that would be required to convince them that Bitcoin has a vastly greater potential than it has yet achieved. Instead of marketing Bitcoin to the people creative enough to see its potential, or to those who so desperately need it now that its benefits are obvious, entrepreneurs like Jeremy Allaire are attempting to market Bitcoin to the average American as a payment-processing system. This is premature because Bitcoin’s benefit as a payment system is only significant after lots of people already have it—therefore the benefit is marginal to most people. As Bitcoin improves, and particularly when it begins to weaken the fiat money system, more and more people will find it prudent to adopt it.

Bitcoin inspires suspicion among bankers and regulators. Bitcoin has a bad image with them, but that’s their problem, not Bitcoin’s problem. Those who are worried about banks boycotting Bitcoin or the government regulating it out of existence should not plan to start a Bitcoin business under such regieme uncertainty. Eventually, Bitcoin will have become so widespread that it will have drastically reduced the scope of both banks and government. Then that will be a good time for payment-processing companies.

This is all a bunch of narcisism. It’s an emphasis on appearance without substance and respectability among people who don’t matter. Bankers aren’t Bitcoin owners yet, and until they are, their opinions are not important. If Jeremy Allaire thinks that Bitcoin has an image problem, he should try smuggling it into Argentina instead of marketing to Americans and bothering with American banks.

How to Improve Bitcoin’s Image

The best way to improve Bitcoin’s image is simply to improve the Bitcoin economy. With every new service, the incentives for more people to join us grows. We should feel lucky that we are in on such a wonderful secret as Bitcoin. If people mistrust and misunderstand it now, then we should be happy if it gives us a little extra time—however brief—to buy more. Every time someone figures out how great Bitcoin really is, he makes Bitcoin even more great by joining in.


_{When you’re an immortal distributed system that can’t be controlled, you don’t have to care what other people think.}

Bitcoin is stronger than all its enemies put together. It is so strong that its image does not matter one bit. It is the 800-pound gorilla that can sleep where it pleases. It is only through timidity, and by failing to see its own strength, that it will bow to outside forces.

1. I wrote this before Mt Gox crashed. I’m very glad it’s gone. Bitcoin still doesn’t need “help” from regulators and bankers.

Instead of letting newbies graduate based on post count and/or time, why not instead let them pass some kind of exam that proves they at least know some of the basics about bitcoin before they are set loose on the forum at large?

It's possible for them to cheat on any test but then if they start stupid threads about issues they should have been clear on in order to pass it, then you can ban them for being obvious trolls who are disrupting the forum instead of engaging in bone fide discussion.

https://blog.conformal.com/redecentralization-robust-developer-network/

As it was originally proposed by Satoshi Nakamoto, Bitcoin was conceived of as a peer-to-peer system that was fundamentally decentralized.  Many past and current discussions about the future of Bitcoin acknowledge that too much centralization is a threat to the Bitcoin network.  To some extent this process of avoiding centralization has been successful, but in several key areas it has not been very successful and it is in need of redecentralization.  The most pressing case for redecentralization in Bitcoin (and cryptocurrencies more generally) is the current development community:

    the number of developers who have experience developing cryptocurrencies is very low, I would estimate there are less than 100 such developers
    the majority of the developers are located in the US and other “Western” nations
    the developer incentive structure with successful cryptocurrencies creates conflicts of interest

In what follows, I propose solutions to these issues cited above.  Since we develop our own full-node Bitcoin implementation, btcd, the criticism of the developer community status quo that follows applies not only to other developers, but also our developers who work on btcd.

This happens often enough that I don't get any benefit from the changes in 0.90. I almost never have a clean shutdown.

Code:

2013-12-25 21:57 (INFO) -- armoryengine.py:10634 - Received new block.  0000000000000002183ed6df1f380c9333f32b1f779e404e60a11bff7968904c                                                                                                  
2013-12-25 21:57 (INFO) -- ArmoryQt.py:4781 - New Block! : 276995                                                                                                                                                                         
2013-12-25 21:57 (INFO) -- ArmoryQt.py:4805 - Current block number: 276995                                                                                                                                                                
2013-12-25 22:12 (INFO) -- ArmoryQt.py:4781 - New Block! : 276996                                                                                                                                                                         
2013-12-25 22:12 (INFO) -- ArmoryQt.py:4805 - Current block number: 276996                                                                                                                                                                
2013-12-25 22:14 (INFO) -- armoryengine.py:10634 - Received new block.  0000000000000000f5263c79ac83062cd24f2c71692de09fc937735a0abef523                                                                                                  
2013-12-25 22:14 (INFO) -- ArmoryQt.py:4781 - New Block! : 276997                                                                                                                                                                         
2013-12-25 22:14 (INFO) -- ArmoryQt.py:4805 - Current block number: 276997                                                                                                                                                                
2013-12-25 22:33 (INFO) -- ArmoryQt.py:4781 - New Block! : 276998                                                                                                                                                                         
2013-12-25 22:33 (INFO) -- ArmoryQt.py:4805 - Current block number: 276998                                                                                                                                                                
2013-12-25 22:41 (INFO) -- ArmoryQt.py:4781 - New Block! : 276999                                                                                                                                                                         
2013-12-25 22:41 (INFO) -- ArmoryQt.py:4805 - Current block number: 276999                                                                                                                                                                
2013-12-25 22:48 (INFO) -- armoryengine.py:10634 - Received new block.  0000000000000001b8a1691057cd6639e56224d99f7f7d80e7b61f55be52d931                                                                                                  
2013-12-25 22:48 (INFO) -- ArmoryQt.py:4781 - New Block! : 277000                                                                                                                                                                         
2013-12-25 22:48 (INFO) -- ArmoryQt.py:4805 - Current block number: 277000                                                                                                                                                                
2013-12-25 22:49 (INFO) -- ArmoryQt.py:4781 - New Block! : 277001                                                                                                                                                                         
2013-12-25 22:49 (INFO) -- ArmoryQt.py:4805 - Current block number: 277001                                                                                                                                                                
2013-12-25 22:51 (INFO) -- armoryengine.py:10634 - Received new block.  000000000000000107ddda65ee3ae1c6d67a96e0c5438e15d5567170ddd849fe
2013-12-25 22:51 (INFO) -- ArmoryQt.py:4781 - New Block! : 277002
2013-12-25 22:51 (INFO) -- ArmoryQt.py:4805 - Current block number: 277002
2013-12-25 23:00 (ERROR) -- armoryengine.py:12372 - Waiting for BDM output that didn't come after 20s.
2013-12-25 23:00 (ERROR) -- armoryengine.py:12373 - BDM state is currently: BlockchainReady
2013-12-25 23:00 (ERROR) -- armoryengine.py:12374 - Called from: armoryengine.py:12563 (94868342)
2013-12-25 23:00 (ERROR) -- armoryengine.py:12375 - BDM currently doing: ZeroConfTxToInsert (85534452)
2013-12-25 23:00 (ERROR) -- armoryengine.py:12376 - Direct traceback
2013-12-25 23:00 (ERROR) -- armoryengine.py:12378 - Traceback:
Traceback (most recent call last):
  File "/usr/lib64/armory/armoryengine.py", line 12368, in waitForOutputIfNecessary
    return self.outputQueue.get(True, self.mtWaitSec)
  File "/usr/lib64/python2.7/Queue.py", line 176, in get
    raise Empty
Empty
2013-12-25 23:00 (ERROR) -- armoryengine.py:13289 - ErrorOut var over-represented number of errors!
2013-12-25 23:00 (ERROR) -- ArmoryQt.py:4725 - Detected Bitcoin-Qt/bitcoind not synchronized
2013-12-25 23:00 (ERROR) -- ArmoryQt.py:4726 - New blocks added in last 5 sec: 277002

I don't see any evidence of problems in bitcoind's logs around the time this happened.

http://themisescircle.org/blog/2013/12/20/mastercoin-is-a-nightmare-of-insanity/

A lot of political and philosophical forums have a versus category. An example of this might be a section of an atheist forum where people can debate religion, or a section of a communism forum where people can debate the free market.

How about adding a child of Bitcoin Discussion called Versus, where all the "Bitcoin is doomed/deflation will destroy us all/my grandmother will never accept it/will be crushed by governments" etc threads can be moved?

How about an optional mode where Armory will throw a warning before executing a transaction any time it's not possible to spend the desired amount of bitcoins without combining inputs from different addresses?

Texas Bitcoin Association is hosting a Bitcoin conference on March 6th, 2014 in Austin, Texas.

This is the Thursday before SXSW, so it's a great opportunity to catch both events in the same weekend.

http://texasbitcoinconference.com