From its 1939 "Nickel, Nickel" jingle to pathbreaking collaborations with Michael Jackson and Madonna to its pair of X Factor commercials in 2011 and 2012, Pepsi-Cola has played a leading role in drawing the American pop music industry into a synergetic relationship with advertising. This idea has been copied successfully by countless other brands over the years, and such commercial collaboration is commonplace today--but how did we get here?...