I remember seeing a urinal with a miniature propeller-like device attached to the grill at the bottom. Using a suitable jet of water, a visitor could make the propeller spin at great speed.

Apparently, these things almost eliminate spillage. The Urinal Fly is a similar concept, much simpler, but not so much fun imo.

I think there's no end to the amount of fun humans can invent. One day, every large company will have a VP of Fun.

  "Our aim is to keep this bathroom clean. Your aim would be appreciated"
  - notice in my grandmother's bathroom.