The wall on which the experiment was done was covered up with white & black stripes. Then using 'deskewing' and some programing they were able to put the projector on the right angle so that the lights moved within the white & black striped wall.
Check out the really cool video:
Hirzberger Events - Digital Wallpaper from Gregor Hofbauer on Vimeo.
This just excites me so much as i hope one day this would be available commercially :)
via [dvice]

























