There's actually an open source project that does this (https://github.com/maxme/bitcoin-arbitrage https://github.com/maxme/bitcoin-arbitrage). It's pretty much

There's actually an open source project that does this (https://github.com/maxme/bitcoin-arbitrage https://github.com/maxme/bitcoin-arbitrage). It's pretty much a simple version of how algorithmic trading works on Wall St. The thing that really kills you is time lag, getting your money between exchanges. This means you can't have pure arbitrage (riskless), but rather statistical arbitrage.