3 part musical from the master geek Joss Whedon

Stars
Neil Patrick Harris (How I met your mother, Doogie Howser)
Nathan Fillion (Mal from Firefly!)

Quote Originally Posted by Blatantly stolen from Wikipedia
Dr. Horrible's Sing-Along Blog is a 40-minute, 3-part musical comedy produced for the Internet, telling the story of a low-rent supervillain, the hero who keeps beating him up, and the cute girl from the laundromat he's too shy to talk to. The movie was written by Joss Whedon and his brothers Zack Whedon (a television writer), Jed Whedon (a composer) and Jed's fiancée, Maurissa Tancharoen (an actress). The writing team penned the musical during the WGA Writer's Strike. The idea was to create something small and inexpensive, yet professionally done, in a way that would circumvent the issues that were being protested during the strike.
Watch it before it goes offline!

http://www.drhorrible.com/