Great news for bitcoin futures traders: BitMEX is now offering convenient trail stop orders on their interface. This is a great way to make sure that when you're in a position that goes into profit, but then whipsaws against you, that the profit is locked in when it goes in your favor. Here's how they describe it:
You set the Quantity of an already existing position in the text field there.
BitMEX has other things in the pipeline too: including an interesting "swap" contract which is currently live on Testnet, which allows you to earn interest on bitcoin while you are holding a position. Stay tuned to hear what these guys have next.