Holy crapsticks Tom Waits. Amazing, incredible musician.
Funny story, the first time I heard one of his songs was on the film Robots, the song Underground was on the soundtrack. I always enjoyed the strange, industrial sound with the odd, rumbling voice, but for a long time never bothered to find out who had done the song or anything else about it. Then, for some reason (boredom, most likely), I happened to look it up, and have since fallen in love with the man's music. The only album I actually own is Rain Dogs, but I've heard a fair bit of his work, and enjoy nearly all of it.