FitnessKeeper

Kinda neat site that helps you track your fitness. It allows you to map your run-routes, gives you estimations on how many calories you lose during your exercise period, and can provide you with analysis of your workouts and post basic information to twitter and facebook.

20$/yr or 5$/mo will make you a RunKeeperElite, unlocking more detailed graphs and analysis.

You can also download a RunKeeper app to take it with you on the go.

REASONS TO USE:
[1] Simple interface / easy to navigate
[2] "Kinda Neat" factor

REASONS TO LOSE:
[1] Not a necessary thing if you aren't constantly active
[2] Costs money for detailed analysis