As the 2010 Winter Olympics start, it is nice to know that the application controlling the thousands of LEDs of the Vancouver Olympic Rings was written in Delphi (although I could not find an external source, I spoke with one of the actual developers). The application controls the ultra-low consumption LED lamps and (as you can see in the video below) can change the color of each forming any kind of effect. You can also read an article here.

Update: I've actually found the video I meant to include, about the rings constructions and technology: