Oh, cute. I like that the design marries the traditional function with the power source. When it comes down to it, this isn't logically different from a badge and a doorknob unlocked by one. The act of inserting a key is familiar, though, and the fact that it doubles as a way to power it is nice.<p>I do wonder how it handles revocation though. After all, if you were to revoke a key, there'd have to be an efficient distribution mechanism or someone could just use it before the lock was updated.