I am a LDraw parts author, and as such I am always interested to find new ways to model LEGO parts. Many parts have a clear geometric structure and are relatively easy to create, but parts like the frog pictured above (note: it's the small green blob) have no defined geometric shape and are very difficult to model. I toyed for a while with the idea of a 3D scanner... The solution came with 2008 LEGO Technic sets that include a new part, the linear actuator. These nifty device convert the rotation movement of a motor into a linear movement. Coupled with the high resolution of NXT encoder, I had all the elements to build a 3D scanner, precise enough for my purpose.There's a video of the scanner after the jump.
http://www.youtube.com/watch?v=Vxm0aThDJHI[Via The NXT Step]