Ladies and Gentlemen, presenting Maut ka Kuan, a.k.a. Death Pit or Well of Death, a inverted cone of wooden planks assembled for the express purpose of driving motorcycles and cars in circles at speeds that make them stick to the walls. The drivers can collect a little cash along the way.
Disappearing Car Door: Damn, this is cool. Everyone will want one. Until the inevitable car accident which renders it unopenable.