Empty business locations cost a lot of money and it is important to keep rental times high. Niklas Roy designed a nice system to attract more attention for an empty shop in Sherbrooke, Quebec. Using the tracking of pedestrians in front of the shop, he moves the rental sign behind the window. Watch the video, pretty entertaining. If you think this is interesting, Niklas' augmented pixel project PING! will also entertain you.

http://www.youtube.com/watch?v=skpS_C0HVik

[Engadget]