Cardboard Modeling
Cardboard modeling is a way of sketching in three dimensions and thus as a tool for (interaction) design.Please see http://www.cardboardmodeling.com/ by Joep Frens.
To start with, you will be in need of a set of basic tools .
Edge blending
Hardware solutions
Matrox PowerDesk for M-Series
Seamless display with multiple projectors using Nvdia GPUs [PDF ]
Software solutions
Multi Projector Soft Edge Blending from edge-blending.com
Kinect
A good starting point is: http://shiffman.net/p5/kinect/
SimpleOpenNI is the way to go for skeleton and gesture tracking.
Projection mapping
Processing
Keystone , a video projection mapping library for Processing. Works with Processing 2. For Processing 3, you need to install it from inside Processing, Menu items: Sketch/Import Library/Add Library, then search for keystone
SurfaceMapper...