I own a 3D printer and hope 3D scanning apps will soon be available.
On the other hand, this demo is showing 3D generation by just filming the object: https://www.youtube.com/watch?v=vEOmzjImsVc
I wonder why this didn't take off.
I think mainly because there isn't much of a usecase for most people.
We use Structure from Motion techniques a lot here where I work (Research Institute) to construct 3D models of buildings and land from UAV imagery.
The current methodologies are great for this use, but they lack the accuracy you'd want to model an object on your desk for 3D printing. That's not to say you can't do it - there's just often a lot of work to be done on the mesh afterwards to make it work.
Autodesk make a pretty good app called 123D catch [0], which uploads your images to their servers for processing.
Alternatively VisualSFM[1] is what I mostly use, I get great results but I don't know how good it is with small things.