When I said "Host your own" I meant on a physically secure box using full disk encryption.
But I do like the idea of encryption, GPG does this really well already but key distribution is still a problem.
Just an idea for a secure physical box:
Throw in a external "always on" GPS receiver on the box and have it physically destroy the hard drive if it is outside of a certain area or if it detects a certain amount of movement (think someone removing it from a rack without disabling the service first). If your server was moved/confiscated it would ensure some safety. Just a tinfoil thought.