First there was this!
(the beer was helpful after ditching my iphone)
John Cage’s Graphic Score
The innovative and influential American composer John Cage created a graphic score called “49 Waltzes for the Five Boroughs” as a tribute to the ever- changing city of New York. He superimposed 49 triangles on a map of New York City, using chance means to determine the locations of each angle. The listener or recorder was invited go to the apex of each angle and listen to or record the sounds of the city in that place.
Rolling Stone Magazine, 1977.