Most 3D scanners around today are built to scan whole objects, however, they don't necessarily do well in scanning parts of an object — like a hand, which is obviously a part of a full body.
A new 3D scanner built by Pieter Smakman, however, can scan a person's hand simply by having them putting it inside of a 3D scanning ring — no need to wave a chunky scanner around.
Not only that, but the scanner itself is built from parts that are relatively easy to get, including a Raspberry Pi mini, a hefty 32 cameras and a few laser pointers.
Smakman calls the scanner Curatio, and it's currently a one-off project, so there are no guarantees that it will ever become something that people can buy. If, however, it does end up being commercially-available, it could become very useful in a range of fields and professions. For example, as noted by Engadget, it could be used to create custom-built casts to fit a user's hand after they've broken a bone. It could also be used to make custom sports equipment, among other things.
All that to say — while you may not ever need one of these 3D scanners in your home, they very well might have an impact on your life.