Up until now, we've focused on the hippie-dippie peacenik aspects of old-timey visions of the future, but what about the military?
The tactical advantages of flying submarines are obvious - they're more flexible than either subs or planes, and they can lie in wait in any body of water, swooping out to attack the enemy when they blunder by. Provided they don't have sonar. But more importantly, they're cool as hell, even if they're amazingly impractical. And undeniably goony-looking. Click through to see.