SSH also checks public keys, without relying on any central signing authority. You could generalize this to SSL easily. You do need to be able to publicize your

SSH also checks public keys, without relying on any central signing authority. You could generalize this to SSL easily. You do need to be able to publicize your public key somehow with as little risk of MiTM as possible, but every secure communication method has this problem. Tor solves this by making a hash of the public key part of the URL. Of course, there might be more user-friendly solutions.