Another application filed by the same team, which includes IBM inventors in Colorado, Michigan, New York and Virginia, also involves fees depending on driver behavior, but this time for drivers themselves, not retailers. It would use proximity sensors to determine the distance between your car and another, and it would monitor how many times you get too close, accounting for things like gridlock. It would also monitor your braking and acceleration habits and average speed. The system could even retrieve your driving history, and use all this data to calculate whether to charge you a toll for your driving behavior. Good drivers could get a rebate.