Lecturefox appears to be a site devoted to gathering all the free lectures from various prominent universities (MIT, Caltech, Harvard, and Carnegie Mellon, just to name a few).

This site is pretty cool, considering it saves one the trouble of looking for all these things themselves. There is a blog, but the home page is actually the lecture list. There also doesn’t appear to be any insane advertising. Just a simple, clean site you should check out if you miss the school days of yore or want to listen in on some good material.