Zeroes and Ones of the Arecibo message put into sound by Professor Ehrhard Behrends, FU Berlin. The Arecibo message was beamed via frequency modulated radio waves into space at a ceremony to mark the remodeling of the Arecibo radio telescope on 16 November 1974. Dr. Frank Drake, then at Cornell University and creator of the famous Drake equation, wrote the message, with help from Carl Sagan, among others.
http://en.wikipedia.org/wiki/Arecibo_message (less info)