Good stuffs to learn OpenID

Here are two video presentations which explain how to use OpenID and the future of OpenID respectively. Both are by Simon Willison.

How to Use OpenID (~5 minutes)
http://video.google.com/videoplay?docid=-7463164786703060643

The Future of OpenID (~35 minutes)
http://video.google.com/videoplay?docid=-3812012811402026027