Star Trek fans will surely remember the replicator, a devices that could re-create just about anything on demand. We're not quite there yet, but 3D printers are a start. These devices typically melt plastic and then carefully layer it, in the manner of a dot matrix printer with a third dimension, until it forms a full object.
The most popular 3D printer today is the MakerBot Thing-o-Matic 3D Printer Kit. At $1200, it doesn't come cheap, and recipients must assemble it themselves, but it's the ultimate gift for a DIY geek.
For: Geeks looking for the next big thing.