Monitoring the Effects of Bad Driving

"For nearly a year, every time a group of Denver drivers stomped on the gas pedal, slammed on the brake or spent an extra minute idling at the curb, the actions were recorded by a device called an accelerometer and assessed for effects on gas consumption."

"The drivers -- half of them city employees and half residents who volunteered for the constant surveillance -- were subjects in a city experiment to see whether motorists would drop aggressive driving habits when they saw how much gasoline they were burning."

"Over seven months, the 400 drivers cut their tailgating, hard braking and speeding -- and improved their gas mileage by 10%, according to results released last week."