The Germans had dozens of fantasy products, some more successful than others. They had machine guns with curved barrels to shoot around corners (actually worked quite well), multiple chamber cannons, anti aircraft wire rockets, magnetic guns, wind guns, sound guns, giant tanks, etc...
The flying wing was indeed conceptually ahead of its time, but the technology to make it viable was just not there. As a matter of fact, were it not for stealth tech, one could say the technology is not there yet. As mentioned before, B2 pilots say their plane handles like a brick when compared to others.
In the end, one of the major German failures of the war was the total lack of research coordination. Everyone and anyone had a pet project, and that led to a fantastic dispersion of resources. So dont be surprised if you hear about "secret" vergeltungswaffen (revenge weapons), let alone new versions of a supposed miracle weapon. After all, the German army did secret research to develop a new helmet in 1943, in spite of hitler's interdiction. If they did this for a helmet, what would they do for a bomber.