I was trying to take advantage of price differences between exchanges. For example: Cex.io is always more expensive than Bitstamp. Does anyone have experience with this? For people in EU, it is easy to work with SEPA and really cost efficient. My idea was to create a circle: buy at Bitstamp, transfer to Cex.io, sell at Cex.io, withdraw cash via SEPA and re-start the cycle at Bitstamp.