TED (Technology, Entertainment, Design) hosts a catalog of speeches, usually 20 minutes or less) of the greatest thinkers in the world today. The speeches are well organized. Some are very technical, others less so, but always stimulating.
I first heard about TED when an email was circulating the talk by Jan Bolte Taylor discussing her stroke. If you don’t do anything else, take 20 minutes to listen to this address. It is the best speech I’ve ever heard.
I always leave the site amazed and thrilled to be living on the planet at this period in time.