In an incredible video presented at SigGraph Asia 2013, researchers demonstrated an amazing new method of deriving full 3D models from only 2D images.
The 3-Sweep software appears easy to use: simply drag your mouse across an image to cue the software to create a 3D model. The specific motion of the mouse drags are the key element: the first drag defines a cross section of a solid element, while the second drag takes that cross-section through a path to "extrude" the solid. Subsequent drags create additional solids that are automatically merged into a complex object.
Once the solid is complete, it can be MOVED AND ROTATED IN THE IMAGE! Yes - you can turn things around in an image. Watch the entire video to see the capabilities of this software.
One aspect we don't yet know about is whether the 3D model can be exported in formats suitable for 3D printing. The software clearly creates usable, solid 3D models that would no doubt work on 3D printers. Perhaps it is a not yet announced feature.
3D modeling with traditional software is difficult for many to learn. This approach, when combined with simple hand drawn objects, could represent a very new and easy to use way to generate printable 3D models.