Tuba By Mathmos

The Tuba by Mathmos creates the illusion of not really knowing whether the central space has depth or not. What looks like a solid illuminated disc in the centre is actually an open space, a void that is brightly illuminated. Mathmos Tuba actually senses your hand entering this void and changes the color or the current function. Alternatively, the Mathmos Tuba can be set to react to music, cycling through a color changing sequence along with the “beat” or your favorite music.

Link