War Tank on One Wheel
Although there is no attribution, we can only guess this came to us from the same guy who dreamt up the Tank Ball.
From Popular Science Magazine, November 1933 - "Housed inside the armored body, the operator will steer the single main wheel by means of two small auxiliary wheels at the rear... by attaching propelling fins to the main wheel, the tank can be turned into an amphibian capable of plunging into a stream... As the tank rushes upon a trench or obstruction, the operator will drop the tubes so they dig into the earth and the whole machine will vault through the air to the other side! Without the armored body or the crutches, it is designed for highway use."
I saw something like this on South Park, only with a few extra "features".