things with wheels that are cool
Easy, this is a tire spinning machine used to spin the front wheels of a car in order to balance the wheel dynamically. The mechanic would place his hand on the fender while this machine would spin the wheel fast enough for him to feel where an imbalance might be located on the rim. He would then stop the machine and place a weight on the rim. The engine power would be used to spin the rear wheel while the other was blocked by a piece of wood.
Shoe polisher :D