I was flipping through YouTube and came across a Joker tribute video with the Scissor Sisters' "I Can't Decide," which is an excellent song for him not only because of the lyrics but the lighthearted, almost circus-like tone of the song. I also found "Mad World" is good for that more somber aspect of Joker we catch glimpses of every so often.
I know Heath Ledger had said he had a punk rock inspiration for the Joker, in particular Sid Vicious, but I don't know any punk, so I don't know what would fit.
What music makes you think of the Joker?
I remember watching an old movie on VHS by Full Moon Productions called "Bad Channels".. In it is a punk rock song called "Manic Depresso" by Sykotik Sinfoney which just fit The Joker so well... and having the band dressed in those costumes it almost seems if they are members of his gang anyway.
http://ie.youtube.com/watch?v=gjuUO3clEjU (http://ie.youtube.com/watch?v=gjuUO3clEjU)
- CrimsonQuill
I love the Scissor Sisters! I never thought of that song being fitting for the Joker, but it really is..
<3 SS
Stuck in the Middle With You by Stealers Wheel
The person who made the Joker tribute video has also made tributes for other characters. They're quite good.