A fun little clip from one of my favorite movies
Why You Got Fat (http://www.youtube.com/watch?v=mNYlIcXynwE&list=UUo79qbil7BXihBa6jfDykxQ&index=22&feature=plcp#)
If you've got 45 minutes to kill, this is an awesome lecture to watch, though for a more entertaining (thought not quite as science heavy) introduction to the theory, watch Fat Head on Netflix or for free on Hulu (Hulu - Fat Head - Watch the full movie now. (http://www.hulu.com/watch/196879/fat-head)).
Science For Smart People (http://www.youtube.com/watch?v=y1RXvBveht0&list=UUo79qbil7BXihBa6jfDykxQ&index=1&feature=plcp#)