Code That Pushed the Language Envelope?

Lil Fritz asks: "Following on from the cool Flash Adventure game last week, this geezer Neil Pearce has written a full client side JavaScript CPU chess player (which drew with me, but then I'm papz at Chess). Now this sort of thing always amazes me. Doing stuff for which it was never intended. Do we have other warped (ie 'they wrote it in what?!?') uses of languages and tools?"