Val Kilmer

Did his own singing while playing Jim Morrison in The Doors (1991). The real members of the band said they had difficulty distinguishing Kilmer's voice from that of Morrison's.

Upon playing Batman: "I've done an absurdly commercial cartoon and now I'm more likely to get hired for a job I couldn't get hired for before, because I hadn't done enough movies. It's so rare when an actor gets hired because he's right for the role - it just doesn't figure into it."