Bill Gross, the 76-year-old billionaire investor, is being sued by his tech entrepreneur neighbor Mark Towfiq for allegedly blasting the theme song from “Gilligan’s Island” into the wee hours of the night, allegedly as a way to cause Towfiq and his wife emotional distress. The spat arose after Gross installed a large glass statue on his Laguna Beach property that was also protected by large nets. Towfiq complained that they blocked his ocean views, and now says Gross is retaliating against him.