Conversation so far:
Are there any other interesting aspects about John Cage?
John Cage is perhaps best known for his 1952 composition 4′33″, which is performed in the absence of deliberate sound.
How was John Cage's 4′33″ project put forth?
Conceived around 1947–48, while the composer was working on Sonatas and Interludes, 4′33″ became for John Cage the epitome of his idea that any sounds may constitute music.
Who were some of the contributors to 4′33″?
In 4′33″ the audience contributes the bulk of the material of the piece. Since the piece consists of exclusively ambient noise, the audience's behavior, their whispers and movements, are essential.

Question: How much did it cost to produce?
Self-contained rewrite: How much did 4′33″ cost to produce?