UC Berkeley Lectures

it's very good, i listened to a whole history course from them a couple years ago

I think Duke has them too, but I'm not sure if it's open to the public (I'm on the faculty there and I've seen it on their intranet site)

It's good that you posted this; I've listened to/watched lectures from several different classes, including physics, biology, and other subjects I've been interested in.

One class I would recommend on there, which I have viewed in its entirety, is "Physics for future presidents" by prof. Richard Muller. It goes over many of the physics 101 type concepts as they apply to current events, and dispels or clears up many of the myths surrounding things like ethanol, global warming, organic foods, nuclear weapons, spy satellites, and other topics. Also includes a good introduction on relativity and quantum mechanics, and how they apply to certain technologies we now use all the time (anybody who's had almost any diagnostic scan done at a hospital owes that service to advances in quantum or particle physics).

Muller's class has been regularly voted as being a favorite class of Berkeley students. It's worth checking out.

Another good one is MIT's 'OpenCourseWare'.

Free Online Course Materials | Courses | MIT OpenCourseWare