Some 3D-printers are actually PRINTED entirely by other 3D-printers! So you can actually create very advanced 3D objects on your 3D printer.
People have printed: acoustic guitars, looms, model vehicles, replacement parts for you car/bike/boat/plane, simple machines, cellphone cases, wallets, shoes, boomerangs, jewelry, dishes, and even clothing.
(check out all cool and FREE 3D printable things on http://www.thingiverse.com)
Okay, so 3D printing is advancing, but it's got to be expensive still, right? Actually prices have come down quite a bit, and 3D printers are about as expensive as a mid-range laptop computer.
The FlashForge 3D printer