MIT, have a of their site devoted called MIT OpenCourseWare to as they put it “Unlocking Knowledge, Empowering Minds” by providing free lecture note, exams and tutorials for their courses. All the courses are available from their site without the need to register and can be used either online or off. I have been thinking for a while of doing a few courses before what ever is left of my ability to learn has dried up and since these are way, way cheaper than the open university option I think I will investigate these and let you know how I get on.