Don't get me wrong I am all for cycling and optimizing trips with your car, but we should also think in another perspective. My pledge is to modify my car as best as possible, to make it greener. I'm going to make it run on alchohol, until I can afford a hydrogen car. We can't let fat oil billioners win. The technology exists, Honda FCX was launched recently, if you are looking for a green car, there is the answer for the near future.