TED (Technology Entertainment Design) is an annual conference […] It defines its mission as “ideas worth spreading”, and selected talks given at TED are available free on its website. Its lectures cover a broad set of topics: science, arts, design, politics, culture, business, global issues, technology, and entertainment.

http://en.wikipedia.org/wiki/TED_(conference)

So many inspiring talks (in Video and Audio format), you will find it really hard to keep listening because the inspiration effect is almost instant.