Richard Feynman's lectures are very popular, entertaining and freely available. There are packaged torrents with lots of videos, audiobooks, pdf notes/essays in them. Lots and lots of stuff to keep you busy.
MIT has lots of excellent material on youtube and on their OCW site. In particular I'd recommend Walter Lewin's physics lectures (8.01 - 8.03), he's a great professor. The Aircraft Systems Engineering (16.885J) course is also worth a watch, it's about the space shuttle's history with ~20 guest speakers each with their own part to play in the shuttle program.