I really need to quote this bit-101 blog post.
It’s the first time I heard about that great website:
I don’t have much more to say about this. Do you need to learn or brush up on any subject related to math? You will find a wealth of data here in a massive number of videos, each 10 minutes or under. Seriously, anything you want to learn is here, from the basics to advanced calculus. Where does this guy find the time?
I got the link from Brook Andrus’ site, where she gives a bit more info on the author. Pretty amazing guy.
UPDATE: There’s another one: http://patrickjmt.com/