First the Wii got us off the couch with its motion-sensing remote; now the Wii Fit takes it to a whole new level with a suite of games exclusively designed to work up a sweat. A wireless balance board incorporates four strain gauges to precisely measure your position. The game's 40 exercises range from yoga and weightlifting to wiggling virtual hula-hoops and slaloming down a mountain. A virtual personal trainer tracks your body-mass index and eggs you on, far from the judging eyes of buff gym rats. $90; nintendo.com
1. At 15, I weighed 210 lbs, little of it muscle. Now, at 24, I weigh 205, little of it fat. The Wii would see a loss of 5 pounds, when I really lost 30 lbs of fat, but gained 25 lbs of muscle. How would the Wii know that?
2. Virtually every Wii game can be played whilst sitting or lying down, moving only the arms. While it's still better than moving only thumbs, it's hardly a difference-maker, in any way.