Brake the right way
1. A car consumes most gas as it accelerates. It's a simply law of physics (force equals mass times acceleration). A moving car doesn't require much gasoline to keep moving (due to the inherent inertia). In real life this means, in order to improve your mileage you need to keep the ride smooth. Let me give you some examples.
About 30% of the drivers I see in somewhat heavy traffic apparently cannot control their speed with the accelerator pad alone. Instead I see those guys speed up and slam on the brakes all the time.