For a mere $39, the Body Check Ball sounds like a dodgy proposition in terms of claiming to calculate your body fat. More so when it states that it can measure your bone density and muscle ratio, all by holding this in your palms. No "Om" chant necessary.
Instead, true to its Japanese origins, the Body Check Ball employs good old technology. A pair of electrodes pass currents from your hand to the ball, which then churns out your health stats onto the LCD panel. Amazingly, this stores up to 10 user profiles and even sports a clock and alarm. Get out of here.
The only hiccup is the four AAA-size batteries, which will cost you more than AA batts and hold less of a charge.