A new Bluetooth-enabled cushion has recently been announced called Darma, which sits on your chair and monitors your posture, pulse, and how long it's been since your last stretch. The connected mobile app extrapolates interesting data like respiration and stress level, and tracks long-term data to help you clean up your habits. Darma even suggests periods of meditation if it detects you're getting particularly stressed out.
Though it might seem goofy to shove Bluetooth 4.0 into just about everything and have it track fitness, considering how much time a lot of us spend sat in front of computers, keeping an eye on posture and making sure we get up and move around regularly is probably a good thing. My only real concern is how comfortable something like this is, but the sensor layer is only 1 mm thin, so it shouldn't be too noticeable.
Darma will be on Kickstarter soon, offering an early bird backer price of $149 and eventually retailing for $249. In the meantime, you can get more information at Darma's website. Anybody interested?