I like to work out because it's a great way to release stress, to get better sleep and to have more energy. Yada yada yada, right? We all know these things are true. But, like most people, I get into ruts when I don't exercise at all. It's soooooo hard to get back on track. But I've discovered a few fun online tools -- which are available for free -- that might help keep you motivated!
Currently I use MapMyFITNESS to track all the exercise I do, minus my bike commuting (more on that later). I'm not going to claim to understand the psychology of why logging every physical activity works, but it does. There's something extremely satisfying about having a record of what you've done to keep you motivated. MapMyFITNESS is far and away the most comprehensive free app I've used to record workouts.