I happened to come across this page on the Berkeley University site which is a list of SWF and RealPlayer .ram files of lectures for the CS 162 Operating Systems and Systems Programming. I’m a big fan of learning about Windows internals and these lectures are great for helping me get more in depth information about the basics of operating systems and to brush up on stuff that I had forgotten since my computer science diploma days.
If you are using iTunes then there are loads of podcasts available from Berkeley, including CS 162. It looks like, starting from 2007, the CS 162 page does not have an MP3 available of each lecture, only the .swf file.
I highly suggest that you check these lectures out.