Hopefully, the streamlined 1938 motorcycle and at least one of the few steam-powered Volkswagens built have survived to this day and repose in some private collection or museum. The 1938 Killinger und Freund streamlined motorcycle did survive World War II, as it was found by American GIs after hostilities had ceased. They took photos of it, though the pictures, published later, weren't very clear.
Probably, you never heard of steam-powered Volkswagens, but they did exist in 1942. These cars were modified by installing a Porsche-designed boiler and steam engine. It was not explained how the wood was inserted for fuel, or where the firewood was stored, perhaps it was kept on the roof rack, just ahead of the spare tire. If things got really rough, maybe the tire was tossed in, too!
The ungainly, bulging hood on this early Beetle gives it away as one of the converted wartime steamers. A number of these cars were converted to burn wood, though the exact count is unknown. In Axis countries, various substitute fuels were tried. Even in the United States, some cars were modified to burn kerosene as a solution to gas rationing.
The first Volkswagen was built in Germany in the mid-1930s, and some of the earliest ones had no rear window! Following that, they had a small two-piece (split) rear window until 1952, and in 1953 adopted a small, ovalish window that was enlarged for 1958.
Volkswagen exports to the United States began in 1949, and during the 1950s and 1960s, VW was the most popular import car in America.