As a co-founder of Fratnimals.co.uk, I am constantly scouring the web for new opportunities to learn and brush up on the skills needed in such a demanding position. In all seriousness, the Mango tool is a free version of Rosetta Stone and uses the same linguistic theory in making it both easy to learn and remember.
The MIT Lecture Browser is great as well-- nice for a lazy Sunday afternoon or if you want to re-learn some things that may have been forgotten...
Come on Berner... you need to start saying you're from Fratnimals.co.uk when you comment on blogs.
Michael Berner
Blake,
Great Ideas. I've been using the MIT site for sometime now. I was shocked when I found out you can take all of their classes for free, just sans diploma. Its a fantastic tool if you need to brush up on a subject.