In 2008, I discovered the Authors@Google series and made it my goal to view or listen to as many lectures and documentaries as I could online during the year. It was a really enjoyable pursuit! I kept a pretty thorough list as I went along, although I should have kept the links along with my notes (would have saved me two hours this morning of re-looking up the videos).
Have to thank saeriellyn who got me started with a helpful little link to The Business of Being Born, and Dmitry Davydov who spurred my enthusiasm on by constantly updating his Best Documentaries blog.
Here's the list of online lectures and documentaries from 2008: