The most effective presentation of skepticism i've seen

Noam Chomsky on postmodernism

Young minds polluted at a museum

This clip is from a Nightline special that addressed faith in America. If you have never seen it before, I want you to pay attention to the way that the Young Earth Creationists use of the concept of worldview to argue that evolution stems from philosophical assumptions. It is also worth mentioning that the museum's curator, Kirk Johnson, now has a very high profile job at the American Museum for Natural History.

The Animated Pale Blue Dot

Biologist debunks intelligent design

For those of you who have  not seen Ken Miller's classic lecture on intelligent design, here it is:

Wally Wallington unknowlingly debunks Ancient Aliens

For more of a full writeup on Ancient Aliens, click here.

Excellent skeptical documentary

The Enemies of Reason is a 2007 skeptical documentary that was hosted by Richard Dawkins and produced by the BBC. It covers many anti-scientific and pseudoscientific beliefs like homeopathy, astrology, spiritualism, dowsing, and postmodernism. If you are looking for a way to get your friends into skepticism, this documentary is fun to watch and highly informative.