Remember those spring-loaded toy cars that you’d pull back to release? Did you ever sit around as a seven-year-old wondering why adults messed around with gasoline or diesel when clearly all you had to do was pull the car back far enough and it could easily travel long distances using no fuel at all? No? Just me and Adrian Roșca of Rosmar H? Cool. Cool, cool, cool. OK, I’m no engineer, and this Audi prototype isn’t using steel springs, but rather compressed air. Yep, the mythical air-powered car.