"Space Invaders 2006 uses a person’s motions to control a video game projected on the facade of a building. Players move their bodies to control an aircraft and shoot down enemies before they descend and vanish off the facade. Dodging and jumping, the pedestrian engages in a game with the building."

Watching the movie is probably the fastest way to understand the project:
http://cca-actions.org/actions/dancing-controls-facade

Detailed project documentation here:
http://www.hawk-huang.com/portfolio/thesis.htm