Free stuff from MIT!

MIT OpenCourseWare
http://ocw.mit.edu/index.html

Well, they've been doing this for a while now, but the Massachusetts Institute of Technology has committed to putting pretty much ALL of their undergraduate and graduate courses' teaching material online, accessible to anyone for free!

Well, it's actually not quite as great as it first sounds, because while the teaching material are available, the teachers are not. So you have lecture slides, but no actual lectures. Some of the courses have pretty comprehensive resources, while some others don't.

But still, it's good stuff.