turn off your car whilst waiting at a red light to save money, something was said about it on the mse e-mail I got as a way to save money on fuel bills.
I personally though it seemed a little silly, can you imagine in the middle of a city on rush hour taking a few seconds longer to move, hello road rage! but seriously wouldnt it use more to start it than to be idiling for a few minutes. In the place I live the light tend not to stay on for very long so by the time you start the car then move, the lights would be red again! seems mad