No, it's not a new military weapon per se. Robert Patterson has developed a wing-like attachement that can be mounted on the roof of most vehicles for the purpose of increasing gas mileage. Being scientifically challenged, I'll just say that it works by creating a vortex in front of the vehicle that uses wind resistance to its advantage; automotive judo, if you will.
Will it double gas mileage as claimed? Remains to be seen. We've all seen a great many inventions come down the pike over the years that were supposed to do that, only to be revealed as ineffective. But if this thing proves itself it could cause quite a stir across the world.
In no time at all the Japanese and Chinese would go to work on them, fine tune them, and sell them to millions of guys like me. Voila; my '83 GMC will get 20 mpg.
A conceivable disadvantage is that tailgaters would become ever more obnoxious as they use their vortex to mess with the car in front.