Very cool: OpenID Server for Movable Type. Just drop it in your Movable Type plugins directory, add one line to your main page’s header, and you can log into any OpenID-enabled site using your own identity, if you don’t have or want to use a TypeKey, LiveJournal, or Vox account.
I’m now accepting comment logins using OpenID, so if you are running your own OpenID server, or have a Vox or LiveJournal account, you can use those identities when you comment (or keep using TypeKey). If you’re already logged in at Vox or LJ, just type in username.vox.com or username.livejournal.com, and the backend will check with that site to make sure you are who you say you are without any need to enter a password.