Lots of great streams from the Norwegian Developers Conference 2009. My favorite is the “HaaHa Show” where Scott Hanselman creates a site and Phil Haack uses XSS exploits. In a later .NET Rocks! podcast (also live from the NDC and available via stream) Phil talks about how the intent was to let people know about the security holes, but he thinks it probably just scared people. I kinda agree, as it is a bit scary to see what Phil was able to do.
NOTE: when I tried to watch the streams they were out of sync and started about 14 minutes in. I am not sure if they have this fixed, but they are still worth checking out.