I love TED Talks ... you can find all sorts of really good (and sometimes fun) talks from some of the worlds most expert people.
Here is an amusing ... but none the less valid ... one I came across on how effective Social Media Networks can be in business.
Enjoy!
http://www.ted.com/talks/alexis_ohanian_how_to_make_a_splash_in_social_media.html
Cheers/Lee