Wikipedia
PlasmaCar
The PlasmaCar is a plastic ride-on toy car designed for children, (can be adapted for adults see below), made popular by Canadian toy distributor PlaSmart. The PlasmaCar can be propelled by wiggling the front steering wheel which is attached to two pivoting wheels touching the ground. It harnesses the natural forces of inertia, centrifugal force, gravity, and friction in order to drive the car forward and backward. It does not require a power source such as batteries, fuel, pedals, or gears - it simply runs on the child's ability to wiggle the steering wheel. It can be operated indoors and/or outdoors, though it works best on a smooth, flat surface.