Okay... so I may end up having to buy one of these because it is just so awesome! If it works as intended.. you can wear the Fitbit 24 hours a day and track everything from how many calories you burned to how restul of a sleep you had the night before (it tracks the tremors generated on your wrist as you enter/exit REM sleep).  VERY cool... if it works as it is meant to I can see this being pretty valuable to maintaining a healthy lifestyle.  For $99 bucks (as of this writing) you buy the hardware... everything else is free.