We already got a bunch of proof-of-work coins and at least one 100% proof-of-stake coin. Is there any other interesting (and viable) concept of proof-of-whatever?

[1st Nxt Slot Machine]

1st Nxt Slot Machine

How it works:

1. Send from 10 to 1000 NXT to [DELETED]
2. Wait for 1 confirmation
3. Look at the last 3 digits of the block id that confirmed the bet

4. If 2 of these digits are the same then you get 3x amount back. If all 3 digits are the same then you get 10x! If you lose you'll get 1 NXT.

Winnings are paid from [DELETED] every 2 minutes.

House can run out of money, so before making a bet check that http://88.198.210.245:7876/?request=getBalance&account=3994117300242888518 shows at least "1000000" in "unconfirmedBalance"!

DISABLED

[Read more about Bitcoin scalability, but do NOT do it on https://en.bitcoin.it/wiki/, other sources are much better for independent point of view.]

Bitcoin has a serious issue which is Scalability. There is no a good solution yet and u should not trust to everything that is written in Wiki (it's edited by earlier adopters who are very interested in selling high). Of course, u shouldn't trust me. So, before u spend all ur life savings it's better to read more about Bitcoin (especially about its limits). Now a lot of people are joining and this will lead to extensive usage and higher transaction volume. When Bitcoin technical implementations hit the wall we'll see a big drop in price, followed by huge cash-outs this will definitely lead to single digits.

It's advice to all newbies: Read more about Bitcoin scalability, but do NOT do it on https://en.bitcoin.it/wiki/, other sources are much better for independent point of view.

Yeah, it costs 7 times more but now it can't be used as currency with all these +/-100 USD swings. Early adopters happy but the rest of the world can't use it even as store of value, because when it crosses 1000 USD mark the early adopters will cash out again. Of coz u can hold it until it reaches 2000 USD mark, but will it?

Distributed Autonomous Corporation is becoming a popular trend. I predict we'll see at least one major scam related to DAC within next 6 months. Be careful.

.

http://blockchain.info/charts/avg-confirmation-time (went up)

&

http://blockchain.info/charts/avg-block-size (less than 256 Kb)

&

http://blockchain.info/unconfirmed-transactions (more than 6000 awaiting transactions)

&

My personal transaction waiting too long


Any ideas how to fix this issue?

[forcing]

https://bitcointalk.org/index.php?topic=334316.0

That thread is about forcing users to use new addresses. Luke-Jr was smart enough to make the thread self-moderated. He removed my comment, so I repost it again:

...unless we force this good behaviour...

I was always thinking u r just a kid who can't predict consequences of his deeds. But now I see u matured. And became more dangerous for Bitcoin. It's very sad to see that sane persons like DeathAndTaxes does support u.

The road to hell is paved with good intentions

I'd like to ask the community: Do u feel it's OK when miners abuse their power forcing ordinary users to do different things (even with good intentions)?

Yes, I know that they call this DEPRIORITIZATION...

[different]

As u know, each time u make a payment Satoshi's client generates a new address to send change to. He (or someone else) also advised to create a new address each time someone needs to receive a payment (for anonymity reason). Entropy of an address is 160 bits (due to RIPEMD-160 "compression"). Applying Birthday Paradox we get that when 2^80 addresses are created we will, likely, get a collision. This is not critical, coz "older" address will be empty, probably. But this can be used in black PR against Bitcoin. An adversary (who is generating addresses non-stop) will be able to show 2 different public keys with the same address. Media will be happy to publish articles with "Bitcoin completely broken" title...

The life is full of trade-offs:
- Risk VS Reward
- Image compression level VS Image quality
- Confirmation time VS Transaction security

The blockchain keeps growing but can we "trade" its big volume for anything else? Storage usually can be substituted by extra computations, but the blockchain can't be compressed well. Any ideas WHAT the bloated blockchain can be paired with?

[sqrt[X]]

From http://arxiv.org/abs/1108.2316 (Merkle Puzzles in a Quantum World):

We showed in an earlier paper that Merkle's schemes are completely insecure against a quantum adversary...

Bitcoin mining algo can be used as Merkle's Puzzle. Does it mean that a quantum computer can find a nonce much faster (sqrt[X] vs X for a classical computer)? I can't find that paper to check this by myself.

Reading this forum I noticed an interesting thing. Bitcoin fanatics (don't confuse with true bitcoiners) are very biased. Arguing about future of Bitcoin they love to mention Internet in 1990s, when almost noone believed that it would become widespread. But if someone else mentions Tulipomania and compares it to Bitcoin, these fanatics becomes very angry and a discussion usually finished with personal insults.

If you are a veteran member of this forum, you already know how many people here are biased. But if you are a newbie, don't think you will meet a lot of sane people here. Most of the users are sockpuppets, keep this in mind...

[squares]

Let's assume that we have a cryptocoin with a 3-block retarget period and 10 minutes between blocks.

A first blockchain looks like:

0th block: timestamp 00:00, difficulty 1   <- first block after retarget
1st block: timestamp 00:05, difficulty 1
2nd block: timestamp 00:10, difficulty 1
3rd block: timestamp 00:20, difficulty 2   <- first block after retarget
4th block: timestamp 00:30, difficulty 2
5th block: timestamp 00:40, difficulty 2

Cumulative difficulty = 1 + 1 + 1 + 2 + 2 + 2 = 9
Hashes calculated (excluding 0th block) = N + N + 2N + 2N + 2N = 8N
Time spent = 00:40 - 00:00 = 40 minutes
Hashpower wasted = 8N / 40 = 0.2N hash/min

A second one looks like:

0th block: timestamp 00:00, difficulty 1   <- first block after retarget
1st block: timestamp 00:10, difficulty 1
2nd block: timestamp 00:20, difficulty 1
3rd block: timestamp 00:30, difficulty 1   <- first block after retarget
4th block: timestamp 00:40, difficulty 1
5th block: timestamp 00:50, difficulty 1
6th block: timestamp 01:00, difficulty 1   <- first block after retarget
7th block: timestamp 01:10, difficulty 1
8th block: timestamp 01:20, difficulty 1

Cumulative difficulty = 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 = 9
Hashes calculated (excluding 0th block) = N + N + N + N + N + N + N + N = 8N
Time spent = 01:20 - 00:00 = 80 minutes
Hashpower wasted = 8N / 80 = 0.1N hash/min

Which blockchain is better? If you take into account the cumulative difficulty you can choose the second one, which looks a bad choice coz it requires hardware with lower "intensity" of hashing. But if we took squares of the difficulty of each block we would definitely choose the first blockchain (15 vs 9).

You may ask why squares? Well... I think there is a mystical connection to http://en.wikipedia.org/wiki/Least_squares.

Right now the most part of ASICs is crunching numbers non-stop trying to mine a block. Graphically this would like a solid line. But let's take a look at the future, when the block subsidy is very small and miners earn money by charging fees. Imagine there are only few transactions awaiting confirmation and their fee is not high enough to waste electricity for mining. In this situation most of ASICs will be switched to a sleeping mode, and the timeline will have a gap. While ASICs are sleeping Bitcoin is "losing" the difficulty, the cost of 51% attack is becoming lower. At some point someone may decide to attempt the attack instead of switching their ASICs off. If they fail they can try again next time if a reward is worth it...

Is it a possible scenario?

[If Ripple validators are shut down due to a DDoS attack, will transactions be processed?]

Simple question:

If Ripple validators are shut down due to a DDoS attack, will transactions be processed?

A lot of hoarders are updating their portfolio. LTC is heading to 1-- USD, time to sell.

No, I'm not going to buy cheap litecoins.

I noticed bitcoind loves to respond with HTTP 500 error. I use "gettransaction" via JSON-RPC, it works only for transactions in my own wallet. Bitcoind could return "HTTP 200: I don't give info about someone else transactions" at least.

Even RTFM won't work coz there is no such a thing...

A brilliant idea - https://bitcointalk.org/index.php?topic=265488.0

I won't be surprised if we see a new wave of altcoins similar to MasterCoin.

[Some fact:]

A friendly advice - read more about the Bitcoin Foundation before joining it. There were a lot of discussions after its launch, if it's good or bad. Time has passed and all threads with criticism were buried under new ones. In my opinion this foundation is a way to earn money to top bitcoin holders, nothing else. But use your own brain to make a decision.

Some fact:

Not all bitcoiners support the Bitcoin Foundation - https://bitcointalk.org/index.php?topic=113509.10
In the very 1st days its founders violated their own by-laws - https://bitcointalk.org/index.php?topic=114911.0
The foundation is ran by a small group of people who know each other very closely - http://dedecentralizationofbitcoin.wordpress.com/2012/10/05/de-decentralization-of-bitcoin/

Too many threads titled that X bitcoins are stolen. What is it? An attempt to spread FUD (Bitcoin is unsecure, blah-blah-blah) or housewives have started using Bitcoin intensively?