Yamaha is introducing its BODiBEAT which they claim is "the first music playback device that synchronizes your music to the movement of your workout." It monitors your pulse and then selects music for you based on the pace of your exercise. The thing costs $300 and has 512MB of flash memory. Although I wonder what it would pick for me while I'm doing my daily workout of bench pressing 800 pounds. Maybe some Yanni? A little Britney Spears perhaps?