The Schlörwagen (nicknamed "Göttinger Egg" or "Pillbug") was a prototype aerodynamic rear-engine passenger vehicle developed by Karl Schlör (1911–1997) and presented to the public at the 1939 Berlin Auto Show. In a test drive with a production vehicle Mercedes 170H as a comparison, the Schlörwagen tested about 135 km/h (84 mph) top speed - 20 km/h (12 mph) faster than the Mercedes; and consumed 8 liters of fuel per 100 kilometers - 20 and 40 percent less fuel than the reference vehicle. According to Karl Schlör, the vehicle could reach a speed of 146 km/h (90 mph).
A year later it was unveiled to the public at the 1939 Berlin Auto Show. Despite generating much publicity, it was perceived by the public as ugly. The project was shelved with the onset of World War II and mass production was never realized.
It never went into production, and the sole prototype has not survived.
📚/📸: Wikipedia, Revivaler