Taking the title as meaning you're specifically interested in the Cold War era – the German military bought some 200 standardised Rlmmp type flat cars from a company called LHB sometime in the 1970s. The letter code should help you find some pictures. They look like normal flat cars, the only difference being Iron Cross markings on both sides. They also bought a great number of unwanted flat cars from the Americans, they're called Talbots in German military parlance and were produced in the late 1950s. I don't remember anything particularly interesting about them, but I'm not a train afficionado, and both types looked the same to me (the American ones were just a little shorter). All cars were owned by the military but stored and...