Gyroscopic Investing

This weekend bitcoin (BTC) had a mini flash-crash - dropping from $30 down to about $10 and now going back up to around $21.  Because the market is so illiquid and small, it seems like there are some great arbitrage opporunities out there:

http://fnoose.com/bitcoin/arbitrage/

Buy BTC at 21.000 USD from Tradehill (USD), sell for 23.356 USD to BitMarket.eu (PLN).
Profit: 11.22%

If you went to a little bit of trouble to setup trading accounts at all of these BTC exchanges, you could make quite a bit of money exploiting these arbitrage opportunities.