This is the Omron HBF-306C Fat Loss Monitor from Amazon.com. It supposedly works by sending a very low current electric charge through the body and calculates the amount of fat verses muscle by the different electrical properties of each of these elements in your body.
You can buy a gift like this for yourself or a very, very good friend, but you might want to think twice about giving it to just anybody. I think it would make a great gag gift to give some friend you want to give a hard time.
A couple of ifs:
If the numbers it displays are scary enough, it might be a good motivator to exercise.
If you keep it up, you might have some impressive numbers to show your friends
If you give this for Christmas, it will get a very big reaction.