Ever wanted to audit a college course online, without having to pay for it? With MIT OpenCourseWare, you can access 1,550 courses on topics ranging from History to Physics and Women's Studies. (Seriously, there's a ton of content here.) It's all free, and it's all available right now -- all you have to do is make time to do the work.
A typical courses includes the basics: a Syllabus, Calendar, Readings, Lecture Notes, Assignments, and Projects. There's even a "Download This Course" link which allows you to take the entire course web site (including all the downloadable files, like readings) with you on the go. Some courses include audio and video content if the PDFs and text aren't doing it for you.
The entire MIT OpenCourseWare system is available free, without even requiring users to register. The amount of content available is staggering, and after nearly six years, the program continues to expand (read the five-year anniversary press release from last April). MIT offers some interesting statistics about the program, for example: "61% of OCW traffic is non-US; East Asia-22%, Western Europe-15%, South Asia-6%, Latin America-5%, other regions-13%"
To get started with MIT OCW, visit the home page, check out the course list, and pick something you like. To learn more about the program and who has used it, read this 2003 Wired article or consult the press coverage archive. If you have used MIT OCW, let us know about it in the comments!