What is your favorite TED talk?
grandalf: This isn't a TED talk but it might as well be.  I found it quite inspiring:Shai Agassi talking about his company Betterplace:http://www.youtube.com/watch?v=SPEwJfSaYmY(Just try to ignore Tim O'Reilly's annoying, negative presence and useless attempts to upstage his guest)