OK, so by now you should know what open source software is (if not, you’re behind–read this to catch up :-). Here’s an interesting extension of the concept to the field of education: OpenCourseWare, which basically means that the professor of a particular course makes certain parts of it publicly available on the internet so anyone anywhere can study on their own however they want. Usually this includes the course syllabus and schedule, as well as various homework assignments and tests (usually with answers). As for the actual course material, sometimes you just have to buy the textbook, but frequently the professor will post lecture notes, presentation slides, or (if you’re really lucky) video or audio lectures.
Several colleges are experimenting with this bold new form of education, but by far the largest is MIT’s OpenCourseWare. They have over 1500 online courses available in nearly every major area of study: biology, chemistry, computer science, economics, history, literature, math, music, physics, political science, writing, etc. (check out the complete list!) Definitely worth a visit, and who know? Maybe you’ll find yourself learning in your spare time!
NOTE: There is also a similar project called Connexions going on at Rice University; they are also worth a look.