Leap Motion is a San Francisco-based startup making a small 3D tracking device compatible with PCs and Macs. The small sensor sits in front of your monitor and tracks movement in a four cubic-feet space around it, which the company claims is 200 times more accurate than any current spatial tracker (like Microsoft's Kinect). In demos given to CNET and The Financial Times, the device was used for precision drawing with a stylus in space, manipulating browser windows, and playing first-person shooter games. The sensors being used haven't been disclosed, but the device's creators claim that its secret sauce lies in having solved mathematical and algorithmic challenges with processing sensor data. Leap Motion has started pre-orders for its $70 desktop tracker with plans to ship at the end of this year--which may be good timing for the launch of touch-control-centric Windows 8.