Zamboni
The Zamboni Ice Resurfacer. If you don't know what it is, you should be shot. I'm serious.
Many of my high school friends know about my Zamboni fascination. At DHS Hockey games, during the intermission I would never go to the snack bar, rather I would critique the technique of the Zamboni driver. The sad part? Usually they did a bad job, and I could explain exactly why, and how, they could improve their technique.