Maybe a bit unexpected... but inevitable.
In 1930s, Germany, the homeland of streamline design, finally accepted the prophetic ideas of Rumpler and Jaray and was busy streamlining almost everything that moved including steam locomotives and passenger planes. Quite naturally, omnibuses (intercity coaches) were also streamlined: the Autobahn programme required a new type of bodywork with low drag co-efficient, allowing for higher speeds and modest fuel consumption. A number of interesting experimental bodies were developed (and some of them built) in 1935-1940. At the headline picture we see a Büssing-NAG streamliner speeding on the A2 Highway, Hannover - Berlin. Let's see some more:
1935 Büssing-NAG 375T (photo via gill4kleuren @ Flickr)
1936 Büssing-NAG 375N (photo via gill4kleuren @ Flickr)
Much more famous coach from the same manufacturers:
Other photos of this type are far less famous (and less atrractive, in my humble opinion):
Yes, it's not the same coach. But nearly similar, save for the front fenders.
And finally, a Ludewig masterpiece: