Wrist Charger lol
surely a battery pack or a battery solution (http://www.bruntonoutdoor.com/
) would give more power and not involve 83g on your wrist.
if the wrist one told the time or also made use of kinetic energy then it might be an alternative but as just a battery seems a little stupid to wear it on your wrist
I dunno.. If the whole device was wrist-mounted, that'd be kinda cool Think Pipboy…
also, those portable power packs are REALLY expensive..