Autodesk has released an iOS version of its staggeringly easy-to-use 3D model generator, 123D Catch.
The tool isn't a 3D scanner, exactly, but the results are similar. You collect a series of images of a 3D subject from many angles, then submit them to 123D Catch for processing. Autodesk's magic algorithms in the sky convert these images into a single, reasonably accurate 3D model. You can then share it among other 123D catch participants or even download it for 3D printing, which is what we're most interested in doing.
There are some constraints, obviously - your subject can't be transparent or too shiny. However, that still leaves a great many possible scanning subjects.
The "bunch of images becomes a model" process is not new; we've seen various iterations of this previously. However, the important part of 123D Catch's use is that it's on your cell phone. In other words, you are likely carrying the equivalent of a fairly capable basic 3D scanner in your pocket right now!
As the popularity of this app increases, we're likely to see a flood of very cool scans. And then the copyright battles begin.