OpenCourseWare is the MIT project to make their class materials available on the web to everyone. Five years ago--on April 4th--MIT announced the OpenCourseWare project:

There are now 1,285 sets of course material available on the OCW web site at http://ocw.mit.edu. There have been nearly 20 million unique visits to MIT OCW content since Oct. 1, 2003. In February alone, there were an average of more than 36,000 visits to the site daily.

"We're getting traffic from virtually every country on earth. From a very simple but profound idea, OCW has grown into a global movement" now used daily by thousands of people worldwide, according to Jon Paul Potts, communications manager for OCW.

Visitors include educators elsewhere (17 percent), students everywhere (32 percent) and a huge audience defined as "self learners" (49 percent).

...via elearningpost