The intent of MIT's OpenCourseWare Project (OCW) is to make available all MIT course materials for free over the web. By October 2003 there should be 250-400 courses available. There are several course management systems in use at MIT, including .LRN / SloanSpace. Course materials flow from the course management system to the OCW repository, which happens to be Microsoft's Content Management Server.
The OCW Content Management System is used to publish the course material to the OCW public web site. There is now a project underway to push the archival course material into DSpace (open source based on J2EE and Postgres).
I have created a mini-diagram.