I'm surprised this hasn't been posted here yet. Or if it has, then sorry about the repeat post, but I've searched and don't find it here anywhere.
This short film is quite excellent:
Batman - Dead End
I definitely recommend the full size movie (160Mb, Mpeg-2, .mpg).
But for those of you on dial-up there is a smaller version available (48Mb, Quicktime, .mov).
Lots of people are calling this the "Best Batman movie ever made!" I don't know about that...in fact I don't think there's ever been a "best" Batman movie ever made...but it is indeed a very cool short film. Well done, nice dramatic lighting and camera shots. And excellent make-up and portrayal of The Joker. Definitely the most realistic Joker ever put to film.