If the market was bigger, 500k would not crash it, as there would be enough buy orders to take someone dumping 500k.

It would still be crashable, but more would be needed if it was bigger.

When the market is really big, then only the really rich people can manipulate it. Comforting thought ;)

It's already a little disturbing to realize that a single account held 261K BTC out of 6.5M BTC in circulation.

I wonder how the distribution of bitcoins compares to that of dollars

I think that someone actually kept that 250k BTC in their MTGox account!

If I'm doing my math right, $500k is something like 2% of the bitcoin economy. Imagine what would happen to wall street if someone cashed out a few trillion dollars' worth of stock at once.

And if "your math" is "number of BitCoins extant time current market value of one BitCoin", your math is not correct. Macha is correct; crashing the market with $500K is proof that the entire MtGox exchange can't be much larger than that, no matter what multiplication says.

Of course MtGox isn't much bigger than $500k per ten minutes. Given how many bitcoins there are and how much each is worth, that kind of volume would be like every cent in the United States changing hands every couple of hours.

You have a terribly flawed idea of how exchanges work and what they are; your logic doesn't flow at all. But I can't really correct that in an HN post.

Entirely possible; I'm writing these before bed after getting home from work. I just have a feeling that if someone tried to convert 2% of the world's USD to rubles in a few seconds without an equivalent transfer in the opposite direction everything would explode. MtGox not being able to handle a transaction like this simply means that there was less than 500k flowing in the opposite direction every ten minutes. If there were, that would imply either a spectacular amount of arbitrage or enough transactions going on inside bitcoin for people to be changing 500k back and forth every ten minutes. This crash just means that neither of those are happening, which I find entirely believable.

and honestly it only dropped for a minute...then it went right back over $14...so even if this had really been legit it would have sorta recovered.