Type Case is a piece by Martin Bircher which uses 125 rectangular "pixels" that are created by setting an LED light in every section of a type case which was used to store letters for a printing press. Close up, it is impossible to tell that the lights turning on and off are showing anything more than random noise, but from a far distance viewers can see that the lights are actually forming text which is from recent headlines.
What I really enjoy about this piece is the necessity for it to be a physical work as it would not have anywhere near the same effect if it were to be, say, a program on a computer screen. It requires a certain degree attention and interactivity from the viewer. The idea of our ability to perceive or process an event based on our distance from it is a compelling one.
One thing I wonder is whether or not most people would be able to recognize the box as a type case, or be able to recognize that the words are headlines and not simply random text. It would be exciting if the headlines were updating in real-time as well. Bircher has also used Type Case to display images as well, but due to the limited pixels I don't find this to be as compelling.