LedgerX is still under development. CBOE is still making annoucements and releasing nothing.
We have a prediction game on LevelTradingField.com that allows you to predict a fall in the price of Bitcoin. While it wouldn't be a perfect hedge to your long position it allows anyone to profit from a fall in the price of Bitcoin. It's a pari-mutuel style system meaning you are actually competing with other people. We limit the participants to 10 people. 3 people are guaranteed to win. The person with the most accurate prediction in the group gets 50%, the 2nd most accurate gets 30% and the 3rd gets 20%. Multiple games run simultaneously.
There are $5, $10,$20,$50 and $100 games. There are also free games.
If you want to jump into trading Bitcoin on one of the exchanges you may want to first try your hand at predicting the Bitcoin prices. that way your losses are pretty minimal in case you really suck at trading.

Try it out and provide feedback. leveltradingfield.com