Fitocracy (free) http://www.fitocracy.com/
Fitocracy is the game you play to improve your fitness. Track your progress, compete against your friends, and get real world results. It’s time to be fitter and look better naked.
RunKeeper (free) http://runkeeper.com/
RunKeeper makes tracking your workouts fun, social, and easy to understand so that you can improve the quality of your fitness.
FitDay (free / $50 year for premium account) http://www.fitday.com/
FitDay is a free online diet journal and calorie tracker trusted by more than 6 Million users around the world.
Whether you're trying to lose weight, looking to maintain a healthy level of fitness, or training for a specific goal, you need FitDay!
Using FitDay is quick and easy. Register for your free account and immediately start taking control of your diet and fitness goals.
Lose It! (free) http://www.loseit.com/
Lose It! uses proven principles of weight loss (tracking and peer support) to help people manage their weight and improve their health. Originally created for the iPhone in 2008 (and downloaded by more than 5 million people), Lose It! is now also available on the web.