"Heartbeats" is an interactive art performance and/or street exhibition which meant to reveal one's personal rhythm -heartbeat- to the public in collective way. It consists of some sets of balloons which has light in it and sensor to detect handler's heartbeat in the end of rope of balloon. Every balloon is capable of reveal each one's heartbeat as blink of light.
(source: www.andrew.cmu.edu/user/noriyuki)