Does anyone have any ideas (or know of a product) for a simple light in a closet that will turn on when the door is open and off when the door is closed?

I do have an outlet in the closet, but a DC method with battery operated lights is fine too.

It doesn't necessarily have to be X-10 compatible. Using X-10 with contacts, Powerflash, Appliance module, and the light would run up to $50+. This is what I'm trying to stay away from.

Roland