Kinect for Xbox 360, Microsoft, $109.99
3D scanning, in which digital 3D models are made from real 3D objects, is the natural compliment to 3D printing, in which real 3D objects are made from digital 3D models. As in desktop publishing, those interested in desktop manufacturing are likely to want a scanner as well as a printer, sooner or later, and probably the cheapest and easiest way to get into 3D scanning at home is the free-for-noncommercial-use ReconstructMe software suite. ReconstructMe allows you to use an off-the-shelf Kinect sensor to produce very high-quality full-color 3D models of objects from about the size of a human hand up to, say, a small car. You don’t need the fancy expensive Kinect for Windows package, either—the plain ol’ Xbox-360 version works just fine. Amazon has a Prime deal for $99.99.