Have you heard of the firefish.io project? These are loans secured by bitcoin executed directly on the bitcoin blockchain using a multisig transaction. There is no third party to handle your bitcoins, but you still need some level of trust in the oracle for the price, or in a liquidator if you default or the value drops below the safe collateral.
Would you use your bitcoin as collateral for a loan in this way?
The service is only available in the pre-access phase for now, but I like the solution.