http://channel9.msdn.com/pdc2008/PC54/ 

Its long, but really very cool.  This guy is the lead for the mono project, which is an open source implimentation of .net.  Microsoft actually gave him a slot at their biggest developer conference of the year. 

One of the really cool bits is something he shows in the middle of the presentation where he talks about the issues that game developers have with the speed of scripting AI in their apps (typically lua).  They can now imbed mono into their apps, and get the features of a fast-performing strongly typed language (c#), but still be relatively 'safe' (memory managment, etc).  He showed a very cool demo of a game construction kit/tool called Unity (i think) which is written in mono. 

Anyways, I thought it was interesting, and if you want to immerse yourself in some pretty technical geeky stuff for a while, it's worth watching.