Dialtones "is a large-scale concert performance whose sounds are wholly produced through the carefully choreographed ringing of the audience’s own mobile phones. Before the concert, participants register their mobile phone numbers at a series of web terminals; in exchange, new ringtone melodies are automatically transmitted to their phones, and their seating assignment tickets are generated. During the concert, the audience’s phones are dialed up by live performers, using custom software which permits as many as 60 phones to ring simultaneously. Because the exact location and tone of each participant’s mobile phone is known in advance, the Dialtones concert is able to present a diverse range of unprecedented sonic phenomena and musically interesting structures, such as waves of polyphony which cascade across the audience. Dialtones was presented at the Ars Electronica Festival in September 2001, and at the Swiss National Exposition in May and June of 2002." [1]

[1] http://www.flong.com/projects/telesymphony/