In particular the end apocalypse sequence (starting at 7:00 min) is amazing.
Update: I'm not wrong in the head! (not about this, anyway :)
A little digging for this post turned up the fact that the animator, Don Hertzfeldt, was nominated for an academy award for this short (which is titled "Rejected"). Apparently it's received over 27 awards, and is the #3 most popular short of all time according to IMDB.