Lets be honest the Nintendo Wii has cornered the market when it comes to Interactive game play, and more importantly sociable game play that includes the whole family (Wii Sports). The Wii fit is a toy yes, and does form part of a gaming console. But don;t be fooled this can give you a serious work out, and will get you fit and in shape (although if you don;t use it for a while it does tell you off, but in a fun way) or you can simply have fun with it, it's up to you.
Personal trainer a system that tracks your wieght and BMI, able to work out any time you wish 24/7, get taught different excercise's, from Yoga, to earobics and muscle work outs. and has a skiing and snow boarding sim chucked in as well, name a gym that can top that, buy this now it's a no brainer.