The 'Forest of Resonating Lamps' is an art exhibit by teamLab that uses sensors and LED lamps to create an interactive swarm of lights.
On display at Maison et Objet 2016, the exhibit lets people walk through a "forest" of hanging lamps suspended from the ceiling. When a lamp senses a person nearby, it will light up with a "tone color." The next nearest lamp will pick up this tone color and emit the same one, and so on down the chain.
The Forest of Resonating Lamps is designed to bring spectators together and encourage them to countenance one another, since the chains of tone colors will always lead back to the people who initially set them off.