volume (in currency) has been growing over the year:

saw this on ogrr:

https://ogrr.com/viewtopic.php?f=268&p=13243#p13243

(not sure if serious. ..)

Someone still needs to find out about Bitcoin:

http://www.engagedigital.com/blog/2009/03/11/yogurtistan-brings-easy-3d-and-stock-options-to-the-browser/

_{Mod note: split again.}

They are distracting and ridiculous., but telling people what to do is annoying as well.

I agree with you on that.
Contrary to what it looks like, I did not start this thread.
I was answering in this thread:  https://bitcointalk.org/index.php?topic=67601.0
Someone deleted my post and created a new thread with it.

I find it abusive. Putting my words out of context is unfair.
It wrongfully suggests that I started the thread.

oh, and we also need a no animated gifs policy.

I compared the last 50 transactions relayed by my Electrum server with the list displayed at http://blockchain.info/ip-address/78.47.154.42

Results:
- accuracy: 36%
- false positive rate: 64%

Technically, it's not too bad, because the number of possible IPs in the network is quite large.
However, I don't think that such a high error rate makes the data useful for any purpose.
Maybe they should publish a list of n IPs that could have relayed the transaction, with a percentage of confidence.

Electrum 0.41 has support for remote wallets.
With this you can generate addresses on a website without leaving the private keys on the server.

This is possible because Electrum uses a "type 2" deterministic wallet;
this means that it is possible to generate new addresses without the wallet seed.

Electrum 0.41 includes two new files:
*remote_wallet.py : a script that is run on a remote server and can be queried with jsonrpc
*remote.php : An example in php. See it live here: http://ecdsa.org/remote.php

Here is how to create and use a remote wallet:

On your local machine, create a new wallet, and create a neutralized copy (without seed):

Code:

$ ./electrum -w mywallet create
$ ./electrum -w mywallet seed | awk '{print $1}'> seedfile
$ cat mywallet | sed "s/`cat seedfile`//g" > neutralized_wallet

Copy the neutralized_wallet to your webserver.
On your webserver, edit the configuration variables in remote_wallet.py (username, password, wallet path).
Then, start the script:

Code:

$ nohup python remote_wallet.py > /var/log/remote_wallet.log &

On your local machine, start Electrum with the --remote option:

Code:

$ ./electrum -w wallet --remote=http://foo:bar@myserver.org:8444

Your local wallet will be synchronized with the remote wallet.
If you visit remote.php on your server, you can create new adresses in the remote wallet.
Everytime a new address is created on the remote wallet, it will show up in the local wallet.

Note that the remote wallet does not need to be connected to an Electrum server.
All this script does is generate new addresses, and tell your local wallet how many it generated.

Recently I proposed to add digital signatures to bitcoin: URIs, in order to proof the identity of the payee (see http://ecdsa.org/bitcoin_URIs.html).
Here is another feature I would like to see added to bitcoin: URIs: expiration dates.

Here is an example: I recently bought a gift order at spendbitcoins.com. The merchant webpage displayed a bitcoin address and asked me to initiate payment within 15 minutes. I guess the 'within 15 minutes' constraint is in order to allow the merchant to delete the token if the customer does not send the money. I think this type of constraint should make it into bitcoin: URI specs. Example:

Code:

bitcoin:19mP9FKrXqL46Si58pHdhGKow88SUPy1V8?amount=1&label=hello&expiration=123456

The expiration date could be a block number or a date.
the expected behaviour is that a Bitcoin client should not send the coins if the URI is expired.

I understand the reason why chargebacks are a bad idea for online commerce.
Bitcoin makes more sense, because it is a system where consumers have to trust the reputation of established sellers, instead of asking sellers to trust random customers.

However, the current system could be improved.
When I place an order, I receive a Bitcoin address from the merchant. At that point, sending my coins to that address remains a leap of faith.

As a buyer, I would feel more comfortable if I had a public proof that I sent coins to that merchant, (not just to an anonymous address), in case of  litigation.

I propose the following:
Instead of simply displaying "Please send <xx> BTC to address <aaa>", the merchant's website should also sign that message with a private key, and give the signature to the customer.
The corresponding public key should be visible on their website. That way, a customer can prove that he actually sent money to the merchant, not just to a random address.

The signed message could also contain the description of the purchased good, and maybe the shipping address of the customer (in that case, customers would lose anonymity if they publish the proof).

Are there online sellers interested in such a solution?
The "signmessage" and "verifymessage" RPC commands of the bitcoin daemon should make this easy. For example, you could use a bitcoin address of your wallet in order to sign messages with it.

Below is a chart of mtgox price and volume.
When looking at volume I usually use a time period of one week in order to smooth out noise.

this week the amount of BTC exchanged was close to 900k, the highest weekly volume ever.



http://bitcoincharts.com/charts/mtgoxUSD#igWeeklyztgSzm1g10zm2g25zvzl

http://blog.p2pfoundation.net/why-bitcoin-is-a-foundational-change-that-won%E2%80%99t-go-away-and-could-change-everything/2011/11/26

http://xkcd.com/980/

The relative market shares of MtGox and TradeHill did not change much since TradeHill was open:
according to bitcoincharts.com, the volume reported on MtgoxUSD in the last 30 days is about 9 times
the volume on thUSD.

I believe that this apparent stability hides a change.

The volume at MtGox is due to a large extent to massive sales of more than 10k bitcoins at once.
When you want to sell that amount of coins, you better go to the market that has the best liquidity.

The volume at tradehill has been increasing lately, which shows that they are able to attract smaller trades.

At some point, the market will run out of very large sales, because these sales tend to distribute bitcoins
among more and  more people. When that happens, the volume at mtgox will be strongly reduced.

my guess is that in 6 months from now, the volume ratio between mtgoxUSD and thUSD will be very
different from 9:1, probably something like 2:1, maybe even less

[receives]

The new Electrum Bitcoin client uses a deterministic wallet. This allows users to recover their complete list of addresses and transaction history from a secret seed.  (except for labels, which are not stored in the blockchain)

For the moment this feature allows users to restore their wallet in case of loss, or to easily transport their wallet on another machine. However, it does not automatically synchronize a wallet that is being used on two different machines. I would like to add this functionality. This would very much ressemble "cloud" services.

The idea, of course, is to use the blockchain as the only source of information; we do not want users to be tied to a third-party storage.

In order to achieve this, the client needs to watch the next addresses that are going to be used in its deterministic sequence. The Electrum wallet actually uses two distinct sequences: one for receiving addresses, one for change addresses. The sequence of receiving addresses might contain gaps (unused addresses), and the maximal size of these gaps is a parameter set by the user. The sequence of change addresses does not have gaps.

The problem of synchronization between two wallets is the following: If bitcoins are received at one of the addresses that are at the end of the current sequence, then the client needs to extend that sequence, in order to know whether the next addresses have been involved in transactions. For this, the client needs to generate new private keys, and therefore it needs the user's password.

So, we are left with the following dilemma: should the client pre-generate the next 100 addresses of its sequence and store them, or should it occasionally ask the user for his password when the wallet receives some bitcoins? both solutions seem awkward to me. Is there a third solution?

UPDATE: this question has been answered below. Version 0.34 of Electrum implements a "type 2" wallet and multiple instances of the same wallets are synchronized automatically.

The new Electrum client uses mnemonic codes to represent random wallet seeds.
A seed is encoded with 12 words from a 1626 words dictionary.
If you lose your wallet, these 12 words are the only thing you need in order to recover it.

Screenshot:

I have installed bitcoinandroid on my telephone, a few months ago.

https://market.android.com/details?id=com.bitcoinandroid&hl=en

today, the application crashes on startup. I have 10 btc on it.
is there a way to recover them?
the comments on the android market page look pretty negative...

all I could find in the sdcard is a "prodnet.blockchain" file.
I guess this is not where the private keys are stored.
does someone know where they are?

[updated october 2012]

Electrum is an easy to use Bitcoin client. It protects you from losing coins in a backup mistake or computer failure, because your wallet can be recovered from a secret phrase that you can write on paper or learn by heart. There is no waiting time when you start the client, because it does not download the Bitcoin blockchain.

Link: http://electrum.org

Features:
*  Safe: Your private keys are encrypted and stored locally.
*  Forgiving: Your wallet can be recovered from a secret seed.
*  Instant on: Your client does not download the blockchain, it uses a remote server.
*  No downtimes: Several public servers are available, you can use any of them.
*  Ubiquitous: You can the same wallet on different computers, all instances remain synchronized.
*  Tested and audited: Electrum is open source and was first released in November 2011.

This animation shows from which point in time coins have moved and stayed unused.

The green curve shows generated coins, the blue curve shows when they were used for the last time.
This is an updated version of an older video

Here is a new service that allows you to annotate the blockchain addresses that you own, or the transactions that you made.

link : http://ecdsa.org/annotate

Only you can annotate your addresses and transactions, because annotations are signed with your private key.
For example, if you donate to a charity of fundraiser, you can now add a message showing who you are.

This service uses the new "signmessage", "verifymessage" commands of bitcoind, available in bitcoin 0.5rc1 (https://bitcointalk.org/index.php?topic=47586.0)

Here is a new qr-code generator using javascript : 

Code:

http://ecdsa.org/qr/<your address here>

Example: http://ecdsa.org/qr/1NrVe3iENN3nJRCH4gaDwa1xBM1Gw3ddLB