Controlling a 3d printer via hand tracking using NITE, OpenNI, OSCeleton, pyOSC, pygame, and the serial sending script from Skeinforge. The code and a full writeup are on my website at http://eclecti.cc/computervision/gestural-printing-jumping-the-shark-on-kinect-hacks . Also, see it in person at the 2011 Bay Area Maker Faire May 21-22!