Hi there,

I've made a multi-touch screen system with a microsoft kinect sensor.
You dont need anything in your hands to control the project screen.

To make this system, you need to :
1. buy a microsoft kinect sensor (Part of xbox 360)
2. Download the microsoft kinect sensor sdk:
http://research.microsoft.com/en-us/um/redmond/projects/kinectsdk/

<a href="http://www.youtube.com/watch?v=amKO-s_cjK4" target="_blank">http://www.youtube.com/watch?v=amKO-s_cjK4</a>

Air multi-touch program
<a href="http://www.youtube.com/watch?v=xk0nAOZTAtQ" target="_blank">http://www.youtube.com/watch?v=xk0nAOZTAtQ</a>