You need a red LED, and a button battery stuffed into the skull. It would be cool if you could somehow rig it so when you took your Razor off the circuit would complete. I am sure someone here could tell you how to do it.
Very very nice!!! Like @Ramaniac wrote, you defintely need a red LED for the skull. In addition you need a deep lough that comes out of hell everytime your took off the razor and / or the brush... Just like this: