MotionMirror (image above) is a mixed reality installation created for a club interior by ZUM KUCKUCK a German design company. The following is a rough translation from the site via babelfish:

In order to underline the atmosphere of a club, movements of the guests / users are abstracted and shown in real time as a mirror projection. The installation employs a webcam, which videos the environment. Software counts the movements within the video and these supply the trigger for the installations movement / animation. On the video screen the movements are shown in abstracted form, each movement is repeated until a new one is registered by the camera.

Below is a image showing the tracking of user movements through the webcam and their resulting abstraction.

Work originally seen here.