Yeah, this probably has already made the rounds, but in case you (like me) have been wrapped up in the mad stress of life and missed it.
Go now and check out Dr. Horrible's Sing Along Blog. It is a 3 part musical, super hero romance brought to you by Joss Whedon (aka The Nerd Messiah) Parts one and two are up and three will be posted shortly. Then the whole thing gets pulled on Sunday the 20th. Trust me on this one, go watch it.