BuzzBack is a project I’ve been working on with the responsive environments group in MIT’s Media Lab.
The project will consist of about a dozen small buzzers, each equipped with a microphone and a speaker. Each one will autonomously listen to it’s environment through the microphone and, based on what it hears, it will sing back a tone through the speaker. The buzzers will hear each other and respond but will also be susceptible to environmental noise like subways or interested viewers.

I’ve been working on a simulation in Processing in parallel to the development of the hardware. You can check it out here. Unfortunately, the microphone doesn’t work in the web app but if your interested in singing to it, you can download the app here.