In 2015, a race among Porsche 911s at the Circuito de Navarra in Spain resulted in this bizarre accident. One car got on top of the sloped hood of another and kept on going, coming to a halt directly on top. This video shows camera footage from the edge of the track, followed by the same scene shot from inside the car on the bottom.
This video shows how befuddled track workers tried to extract the driver in the top car, as well as safely remove his car from the stack. They ultimately brought in a crane to haul the top car off.
-via Laughing Squid