NASA Looks At Cleaner Engines
One of the least favourite memories of visiting an airport is the smell of kerosene burning. NASA as you can image continues to spend millions looking at alternative ways to move us from A to B. This page on their website looks at how to achieve cleaner skies.
What I like about this type of research is the technology spin offs. After all sending a man to the moon in the 1960s brought us the non-stick frying pan amongst many other technologies. So who knows. One day we may be able to power our cars by dropping banana skins into the fuel tanks.