Nissan is planning to sell cars that push back on their gas pedals when they feel drivers are speeding up too quickly. It will be available next year, and I will not be buying a Nissan. The idea is to increase gas mileage and efficiency, but aren't there already enough people out there who slow down traffic by taking as long as possible to get up to speed? A special gauge on the dashboard changes color and flashes when drivers aren't accelerating "optimally", but a grille pressed into their bumper by the angry person behind them may prove to be more compelling. Fortunately, the feature can be turned off.