John Lennon suspected that he was being monitored by the FBI, so he would go to his neighbor's house when he needed to make a sensitive (anti-war) phone call. His suspicions were indeed true, as discovered in recently freed FBI files, in politically motivated violations of Lennon's rights. Anyway, Lennon's phone neighbor? John Cage, the composer famous for 4'33" of silence.
Randy Newman, the popular folksy song composer, is a direct descendent of Nikolai Rimsky-Korsakov, the famous Russian classical composer (Flight of the Bumblebee is probably is most well-known work).