750 online college courses from some of the most prestigious universities and professors in the US and UK, available as online courses or iTunes downloads. Of course, there is no credit attached to them and you won’t earn any degree. However, if you want to enhance your learning with the real deal but have no money, this is the place to go.
For the truly intellectually promiscuous OpenCulture offers everything from astrophysics to engineering, psychology to law and more. It also links to other free learning experiences, like free language classes, free kids classes, free movies and free textbooks.
I like that. A lot. Knowledge and learning available to anyone with access to a computer for free. There are even free certification courses available.