Garmin Forerunner

No more guessing—or fudging—the length of this morning's run with these devices from Garmin (GRMN). They range in price from $150 to $350 and use the Global Positioning System fleet of satellites to tell the unvarnished truth about how far you've come. Forerunner devices can be worn on a wrist and track the wearer's heart rate while measuring distance.