It controlled lights. IIRC there was a grid of squares on the website that you could click on to turn specific lights on or off. There was a webcam pointed at t

It controlled lights. IIRC there was a grid of squares on the website that you could click on to turn specific lights on or off. There was a webcam pointed at the sign that refreshed every few seconds so you could see the changes. I remember the sign being right above an escalator.