[ravenus]

Uhhh..if you really read The Killing Joke, the Joker doesn't do what he does to Comm. Gordon because he thinks it's funny. He is openly sadistic and wants the man to completely lose his sanity, and make the world thereby realize that anybody under a defined set of circumstances could have become the Joker. That's not a funnyman cracking a macabre joke, that's white hot rage.