Notes in the Shower

They say it's good to keep a pen and paper on your nightstand so you can record ideas you have before you go to bed or when you wake up.  I seem to have more good ideas in the morning when I'm in the shower where pad and pencil are sure to fail.  I'm thinking a white board with a marker that is waterproof but not alcohol proof.  You would be able to take notes in the hot water and when you need to clean off you board you could use isopropyl alcohol to erase your shower genius.