Are you looking for something like futures? If so then you might as well use margin trading (it really is the same thing as trading futures, with only technical differences), which is allowed at btc-e and bitfinex. If you are looking for options then you can try updown.bt which allows binary options on a number of markets.
How is trading on margin the same as trading futures?
Trading on margin is trading on borrowed money. Trading futures is making a bet one which direction the price of the investment will go in the future.
Trading on margin required trader to pay interest on daily or monthly basis. Trading future has build in interest where the spread will become smaller as it approaches expiration date.
Both are essentially same thing with different borrowing rate.