I may buy one Nintendo Wii take a look at the results from Mickey DeLorenzo experiment:

After 45 days, he managed to shed a full 15 pounds, or about 2.56 pounds a week, and he dropped his body fat % from 20.8% to 18.4%.

"I LOST 15 lbs. IN 41 DAYS JUST BY ADDING WII FIT TO MY DAILY ROUTINE!"

Take a look:

The Wii Fit Experiment - Workout Montage from WiiNintendo.net on Vimeo.

More information about Nintendo Wii Fit here:
http://www.nintendo.com/wiifit/launch/?ref=http://www.nintendo.com/wii