In 2008, the next Batman movie, titled The Dark Knight, will be released. I'm excited. In this story, Batman (Christian Bale) will square off against the Joker (Heath Ledger). The Joker portrayed by Ledger looks much darker and scarier than his previous incarnations, even the drawn ones. Check it out.
Here's a drawing of the Joker. It's the darkest and scariest I could find from a 3 second perusal of some google image search results:
Here's Cesar Romero as the Joker in the campy Batman tv show:
Here's Jack Nicholson as the Joker in the 1989 Batman movie:
Finally, here's Heath Ledger as the Joker in the upcoming movie. I love that his "smile" is actually scar tissue from, what looks to be, a nasty knife wound: