They do exist but I don't know about their efficiency.
However, a young man in B.C. has developed an excellent glow-in-the dark reflective sticker called E-Z Find that he has produced in a number of different forms. One is a little round ring that sticks around your car keyhole. Expose it to normal sunlight, and your keyhole lights up all night long.
He has several forms for light switches and the like, as well as a large square patch that you can use as is or cut it to the shape you want. This one works really well by attaching it to the zipper handle of a camping tent -- you can always find that zipper any time of the night. Just fold the self sticking reflector over a wire triangle, much like the ski tickets we attach to our coats. You could also put one on the handle of your flashlight to help you find it in the dark.
This is really a great little invention. If anyone wants to help him market it, drop me a line.