This idea might be crazy, but it's certainly worth thinking about. A group of Welsh scientists have developed a box you attach to your muffler that stores the carbon from your car. When you get new gas, you change boxes, and the gas in your old box gets eaten by algae (we imagine there is a more scientific explanation to it. Those are the layman's terms.) As with most of these world-saving inventions, it's probably too good to be true. But if, in 20 years, you have to change your CO2 box at the gas station, you heard it here first.