Ask Slashdot:Linux Vending Machines?

Joey wrote in to ask "I'm currently working on a project to turn a Linux box into a Juke Box running Mp3's. But I'm faced with several problems, it has to be coin operated (i was just told it has to use brasilian dollar bills), have an interface anyone could use, and be stable. If someone could help me out with ideas and where to get the money validators I would really appreciate it."