This is a great talk. I know that very few of you will think that you want to watch an hour long video on cosmology. However, give the guy 5 minutes and I will be very surprised if you don't watch the whole thing.
It starts with a very brief intro by Richard Dawkins but the rest is done by a very smart, very clear, and quite funny guy named Lawrence Krauss.
Oh, by the way, if you are a religious zealot of any kind, you won't like it.