I heart fiber optics.
In a blitzingly cool move, a bathroom fixture company has produced the ELS (or "Electronic Light Shower") -- a shower head that streams both water and light. Brings a new meaning to the phrase "bathed with light"!
You can pick a single color, or let the halogens run through a continuous cycle of different colors. I'm a little annoyed that they felt the need to encrust the thing with Swarovski crystals: Link