Oh sure, we've seen gadgets used as motivational tools before, but Sega Toys is apparently banking on you not being a hothead. Otherwise, you just might fling its Body Trainer headset from your dome as soon as you hear "please exercise a little bit harder" over your incessant panting. Nevertheless, those with oodles of self-control may actually benefit from having a personal trainer (of sorts) in their ear while working out, and by monitoring the wearer's heartbeat via a sensor, it can blurt out messages at the appropriate time to help users through their session(s). Reportedly, this nifty exercise buddy is set to launch in Japan this April for ¥5,775 ($54), and while we've no idea if t ...