Looks like you guys havent heard of Bubble cars.
Have a look. great history.
http://en.wikipedia.org/wiki/Bubble_car
These cars were made post world war. Fuel prices skyrocketing, this was the logical option. small cars that were cheap, economical, and used two wheeler parts mainly.
Messerschmitt was the company to start it all.
had cars with inresting mechanics too.
early cars did not have reverse, and had hand operated controls ala our autos
But later editions had a special mechanism to start the small two stroke engine in reverse, so u get 4 speed reverse!!!
and even more upgareds saw the advent of steering wheels and foot pedals, and this is whem BMW jumped in.