Suunto Ambit2 S

The Ambit is an adventuring watch that gets wet. Since it has a built-in accelerometer for measuring stroke rate, waterproof capabilities to 50 meters, and superfast GPS pickup, it's the only watch on this page we would wear in the lap lane or ocean. A triathlon mode lets you switch between the three disciplines. [$400 (with heart-rate strap); suunto.com]