Mark Ecko, of Ecko Unlimited, is designing "digital citylights" that people can interact with using their cell phones via Bluetooth interface. You walk up to one of these monster LCD screens and spray digital graffiti with the cursor of your phone. Allegedly they're going to be released in Germany
The Landmark Bus Shelter was designed by a German company for use around Hamburg in an attempt to "convey a harmonious overall image of the urban area. Modern elements and clear lines enable a universal use of this bus shelter. The right side wall contains a lighting system that shines in changing colors. This provides for alternating light and color moods at night.
M. Sharifi, T. Payne, and E. David. Mobile Interaction with the Real World (MIRW 2006) in conjunction with the 8th International Conference on Human Computer Interaction with Mobile Devices and Services, Espoo, Finland, (September 2006)
B. Brown, and M. Chalmers. ECSCW'03: Proceedings of the eighth conference on European Conference on Computer Supported Cooperative Work, page 335--354. Norwell, MA, USA, Kluwer Academic Publishers, (2003)
C. Graham, K. Cheverst, M. Rouncefield, and C. Kray. DUX '05: Proceedings of the 2005 conference on Designing for User eXperience, page 18. New York, NY, USA, AIGA: American Institute of Graphic Arts, (2005)
P. Holleis, E. Rukzio, F. Otto, and A. Schmidt. Mobile Spatial Interaction in conjunction with ACM International Conference on Human Factors in Computing Systems CHI 2007 - Reach Beyond, San Jose, California, USA, (April 2007)