The Ubi Displays toolkit (https://code.google.com/p/ubidisplays/) being used to create two sided transparent multi touch screen which also responds to finger snapping!
You can read more about it here: http://highwire-dtc.com/ubidisplays/community/viewtopic.php?f=3&t=6
Earlier Video: http://www.youtube.com/watch?v=BOTbbx95Qp0
Dragon Video: https://www.youtube.com/watch?v=oov6iB_4epo
Ubi Displays Video: http://www.youtube.com/watch?v=df1NO7MoAUY
The vision behind Ubi Displays is to enable more people to quickly try out ideas and see what sticks! If you are using Ubi Displays to make creative computer interfaces, please share them here: http://highwire-dtc.com/ubidisplays/community