If you're interested in tracking your activity levels, you can always write down your workout and try to figure out how many calories you burned walking from your desk to the refrigerator at work. Or, you could purchase a gadget (and who doesn't love gadgets?) that will monitor all of that for you, and more.

One of the newest gadgets on the market is the Fitbit. Well, it's not even really on the market yet -- it's just available for pre-order, and won't start shipping until late December or early January.

But, they say it's worth the wait. Why? Several reasons, after the jump:

• Size -- It's teeny tiny, so you don't have to worry about hauling around any bulky equipment.
• Accuracy -- The Fitbit has been tested on people of all shapes and sizes and it appears it's a really accurate pedometer.
• Multi-use -- It not only tracks calories, but also your sleep habits, so you can learn more about your sleeping patterns.
  
• Simplicity -- The wireless system means that, as long as you're within 25 to 50 feet of the provided base station, your data will automatically be uploaded to your PC or Mac.
• Results -- The website is available for anyone who purchases the Fitbit, and helps you analyze your results and share information with other users, which helps with motivation.
• Price -- All of this will be available for under $100!

So, we're talking about an affordable, matchbook-sized gadget that can be worn on almost any part of your body that'll track the intensity of your workouts, steps taken, distance traveled, calories burned, and quality of sleep? My curiostiy is piqued, to be sure. If you're interested, you can pre-order here (your card won't be charged until the device ships) or you can simply request that they let you know when Fitbit becomes available.