TED.com: Excellent lecture site
TED.com (stands for Technology, Entertainment, Design) hosts lectures by some of the top minds of the world. Their best lectures are available for full and free viewing online.
To see an incredible lecture from their program about how the human brain functions, by a leading brain researcher from Harvard, cut and paste or click this link http://www.ted.com/index.php/talks/view/id/229
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