Air — it's not just for breathing anymore!

Just when we all thought oxygen couldn't get more lame and boring, the boffins at Peugeot Citroen have found a new use for it. They recently unveiled their Hybrid Air Concept that replaces batteries with tanks of compressed air.

Here's how it works: You've got a traditional gasoline engine up front, but instead of batteries and an electric motor like on a normal hybrid, there are tanks of compressed air connected to a hydraulic motor and pump. The compressed air can drive the vehicle up to about 44 mph before the gasoline engine takes over. It can also work in conjunction with the gas engine. If it needs more air, it just sucks it in from the outside.

According to Gizmag, this means that the compressed air system can get up to 81 mpg with greatly reduced CO2 emissions. The other benefit, PSA Peugeot Citroen says, is that it's quite a bit cheaper and less mechanically complex than traditional battery-powered hybrid systems.

It's a clever system, and it sounds more feasible than other attempts at making air-powered cars, none of which have ever really gotten off the ground. Peugeot Citroen claims they're serious about putting this on actual cars by 2016, and they say it can be easily adapted to their existing cars.

Maybe they'll pull it off. After all, Citroen already runs a diesel hybrid car, and many critics said that would be too expensive to ever be viable in the marketplace. Time will tell if this new concept is the real deal or if it's just hot air. (Hey-oooo!)