I appreciate your efforts towards easy, secure and anonymous authentications.  It is frustrating to remember so many passwords, and I never like using the same password because I never know if the server is actually hashing them!

I think the future of authentication will be ECDSA signing tags like the sigsafe NFC tag.  The server would generate a random nonce, relay the nonce to the client, and then the client's browser would request an ECDSA signature from the user.  With HTML5 and the Web NFC API (which is not yet ready), the browser would have access to the NFC reader.  The user would tap his signing tag, the tag would sign the nonce, and the browser would then relay the signature back to the server.  The user is now authenticated (perhaps using the bitID protocol).

The beauty of this technique is that the user can use the same signing tag (and same private key) for multiple services, as the services can only verify signatures (they can't forge them).  

It looks like the mozilla has a prototype browser that can exchange NDEF messages with a NFC reader and HTML5.  If you guys can get this working, we could use the sigsafe tag that I'm working on to produce the signatures.