I saw a video on YouTube showing a wall filled with iPods. There are 20 iPods on this wall all connected via Wi-Fi. All of them are running the same application at the same time. If you touch one of the iPods it affects all the other iPods. It becomes some kind of a chain reaction. For instance this reaction can be a sound or a picture.
If you want to see this wall yourself, you’ll have to travel to Tokyo. You walk into this wall when you enter the “Prototype design-house”.

Source: Gozmodo