Richard J.D. Stokes had a brainstorm in 1949: Why waste energy maintaining both a car and a washing machine when you can attach a washtub to one of the car’s wheels?

Pour water and soap through the opening in the watertight container and drive at a low speed to wash your clothes, then drain the water and drive a second leg to dry them.

Stokes envisioned that his invention would be useful to “campers, those who live in trailers, and other travelers” — but it might also appeal to fleeing murderers with bloodstained clothing.