[ConceitedCode]

The biggest issue I see would be updating the block chain for the wallet between uses. Seems like it takes longer and longer to update. Moved my wallet to a new computer last night and it's been going for the last 5 hours.

[pilgrim689]

A workaround: the device you connect to has a bitcoin client running just to keep the block chain up to date. The USB key, upon connecting, syncs that block chain with the one stored on the key. When you connect to a new device, the block chain from the key is synced onto that new device. Depending on how often you switch device / how often you use the key, this might or might not be a useful workaround :P.

[nwh]

Even synching the block chain that is a few hours old is irritating, days or weeks old would be a nightmare.

[cookiecaper]

If you download the blockchain from the P2P wallet client it always takes forever. You should download the blockchain once, put it on a USB drive, and then copy it into .bitcoin before you bootstrap a new machine with a wallet.

There are also sites that offer downloads of tar'd versions of the blockchain, or torrents. Pretty much anything is going to be faster than downloading via a bitcoin client.

[tripzilch]

This thread appears to have a download/torrent for a recent version of the blockchain data. It's about 4.7GB, apparently.

https://bitcointalk.org/index.php?topic=145386.0

So does that mean if you're not using BC via a wallet service, it requires at least 4.7GB of disk space in order to do its thing? How is this amount of data expected to grow in the future?

[lmm]

It's going to grow hugely (at least as long as punters keep using bitcoin); there's an expectation that clients will switch away from using the full history sooner or later, and there are mechanisms prepared for remaining reasonably secure with shorter histories.

[sliverstorm]

Hah, so eventually only a few people like central power figures in the bitcoin community will be running with the full blockchain eh? Probably my favorite thing about bitcoin is how, despite its explicit goals, the more adoption it sees the more it looks like it will turn into the same old thing we already have.

[lmm]

I remember a friend making a similar comment about EVE online: you set people loose in this anarchistic, libertarian blank state, give them a few years, and... turns out they'll band together into gangs with leaders, that develop into communities with formal governance processes; neighbours helping each other out grows into insurance syndicates....

We've already seen people wanting an authority to compensate them when their bitcoins are stolen; bitcoins are meant to behave like cash, but an FDICed bank account is much more useful than cash for most people. That said, as long as the full feed remains open to anyone who has the spare compute power/disk space and wants to connect up to it, there's still a big difference from the existing financial system.

[nwh]

That's not even a large portion of the blockchain anymore. The full thing is 7GB now, and most of the large transactions are in the very recent bit.

[unreal37]

Nothing possibly could go wrong downloading the blockchain from a torrent site....

[Groxx]

This is basically true, actually. It'll either work or it won't, and you're just out of the bandwidth if it fails verification. At the absolute worst, you won't be able to accept any blocks from the network as a whole if it's fake, because the hashes won't line up. IIRC the official client (and most others) also include a hard-coded hash part way through the chain to help ensure you're on the correct one up to that point.

That's of course assuming there isn't some exploit in your client, due to e.g. unsafe reading of the file that could allow it to execute arbitrary code hidden in the blockchain file.

[tripzilch]

According to the thread I linked above, the software verifies the data during import.

[psionski]

Blockchain.info wallets are pretty nice, they do client-side encryption with separate log-in and spending passwords (so your private key is encrypted inside an encrypted .json file and the first password decrypts only the outer layer).

You also get email (or dropbox or file download) backups that you can use in other Bitcoin clients in case something bad happens to blockchain.info.