Javier GalÃ¡n (a.k.a. Chronoh) created a very slick demo reel with great timing and cool music. Though it has a Flash feel to it, it was done in Blender.
You can view it via the links on his website or the Blender Artist thread
[ev type="youtube" data="http://www.youtube.com/watch?v=oNLtTFm9eMY"][/ev]