LM3LABS has created gesture controlled Hologram system called AirStrike, which is controlled by arms and hands movements . More about the holograms via greatdance.com
Gesture-controlled hologram
eyeSequencer creates ambient music from the human iris
"Every now and then you see some particullary beautiful eyes ... some of them inspired me to use images of eyes to create musical material. I wrote a little framework/application in Processing to help me analyse the image. "Scanners" circulate in the eye and analyse RGB and brightness values. These values are used to create OSC Messages, which then are send to SuperCollider. SuperCollider would be a great way to produce the sound, but for this example i decided to use SC3 to send MIDI events to Ableton Live, to two instances of the Alphakanal Automat Synthesizer" Patrick Cappel
The EyeWriter on Instructables
I previously mention EyeWriter in the "The EyeWriter /inspiration to share". The information on haw to build this eye-tracking apparatus is available on Instructables which is grate place to search for technical solutions of all kind.