Sonoplastic

http://cycling74.com/project/sonoplastic/ 
I chose this interactive art piece because it to me was really interesting the way that it reacted so well to how the user was doing everything as well as have some very interesting visual effects.  This interface is really interesting because judging from the video it used a combo of laptop management and a very specific recognition of the gestures the user uses as well as what looks to be like a lot of height awareness.  It fits into the theme of this course because of how it uses such spacial and movement awareness, and as the creator says it will take in multiple people and change in accordance to normal and natural body movement.