when i was looking for a sleep monitor, i considered fitbit and wakemate. wakemate uses bluetooth and its battery lasts about 24 hours (about 3 nights).
the fitbit tracker uses ant+ and its battery lasts a week or two, even with all of the extra monitoring it does throughout the day (as a pedometer) and wireless synching every time i'm near the base station. i was going so long between charges that i'd forget about it, so i made the fitbit low battery notifier (http://fitbit.jcs.org/) to send me a text message when the battery was low.
from what i've heard, fitbit will be extending their products to include heartrate monitors and other things using ant+.
There is an OpenChronos firmware extension which contains a sleep phase detector. Apparently (I haven't checked it) it works in connection with a PC running a clock program.
the fitbit tracker uses ant+ and its battery lasts a week or two, even with all of the extra monitoring it does throughout the day (as a pedometer) and wireless synching every time i'm near the base station. i was going so long between charges that i'd forget about it, so i made the fitbit low battery notifier (http://fitbit.jcs.org/) to send me a text message when the battery was low.
from what i've heard, fitbit will be extending their products to include heartrate monitors and other things using ant+.