The bike equivalent of RunKeeper. Strava's user-friendly interface lets you track, analyze, upload, and chart everything from estimated watts to total elevation gain for the year. Cooler still, you can opt in and compare your data to everyone else's in your network. It also has a nifty search function that allows you to quickly find the most competitive routes and see how their toughest climbs rate, from cat 4 through hors categorie. Free; Android, iPhone, and Garmin.