During the PASSAGEN 2011 in Cologne students of the new master program “Kommunikation im Raum” FH Mainz were showing the interactive light installation ‚Interactive Kölsch‘. In the basement of the hotel ‚Monte Christo‘ 1600 individually controllable LED lights transformed the room into a stunning spatial experience. The visitors were able to influence the installation via their Kölsch consumption. When buying a drink they were handed over a beer mat which had a pattern, a so called marker, printed on the back side. Two different beer mats were available – the first one labeled with ‚blue‘, the second one with ‚pink‘. With these beer mats the installation could be controlled and influenced in the corresponding colours via an ‚interactive-table‘ .A camera which was installed in the the base of the table recognized the marker through the overlying acrylic glass pane. This camera transmitted information like quantity and position of the particular markers to a connected computer.