I am very impressed with Stanford. They are opening up several courses to the public using online participation (including video), for free.
Two classes that are relevant to my area are AI and Machine Learning. Both will for sure be outstanding. The first is taught by Sebastian Thrun and Peter Norvig – both leading researchers in AI. The second is taught by Andrew Ng who is also an outstanding researcher. I also believe all three are excellent teachers.
58,000 people already registered for the AI class. What a nice opportunity for grad students, but also for undergrads, highschool students, professionals, and retired people.