We have seen the future, and it’s a gas. Witness the many mind-blowing concept cars revealed in two-­dimensional form at this year’s Greater Los Angeles Auto Show Ultimate L.A. Machine contest with Design Los Angeles. Highlights include BMW’s California Spyder Concept (featuring a 700-horsepower V-10 engine and a retractable carbon-fiber top) and Honda’s C2C, a lightweight hybrid rider with an aesthetic straight out of Tron. Also awe-inspiring: Hummer’s podlike Hr, Mazda’s rotary-powered single-seat Shinzui, and Mercedes-Benz’s Flügel Tue — a fan-propelled flying sedan. Honk if you’re already hyperventilating. — S.S.