Surprisingly, I haven't seen much talk of the FitBit around here. I've already bought one so I'd pretty much just like to throw it into the mix of Products You Should Definitely Consider Buying
The FitBit is a $99 USD glorified pedometer. It will track your steps, calories, distance and overall activity level every day you wear it. It can track how fast you fall asleep, how often you wake up during sleep and how much net sleep you get.
I got my FitBit after deciding that a Bodybugg was simply out of my price range. I knew I wanted to make a change but couldn't commit to that kind of cost for the hardware or the program. So I did a bit of research and fell in love with the specs of the FitBit and its slick design.
I've been using it for a full month now and I've got to say that I'm impressed. I wear mine on my bra of every day and on my wrist at night. I've gotten a much better sense of my general activity level and how much I'm really working during my workouts. I also log my food on the FitBit website in a similar fashion to Daily Plate/SparkPeople/other trackers. I can look at graphs of my sleep/weight/BMI/distance/calories/activity level over time. Although I haven't made any significant changes since getting the FitBit I still like being able to watch my trends. And the data is shareable; you can choose what to show (to the public and to FitBit friends) and what to keep private.
Basically, I think the FitBit is a great investment. It may not be 100% accurate on every count, but it's an amazing deal for the price.
If you're curious about the stats, you can check out my page: http://www.fitbit.com/user/22C8HX