In addition to playing the trombone, he also performed in skits such as "In the Year 2000." He was also commonly the butt of Conan O'Brien's jokes during his monologues or interviews in which Rosenberg was often implied to be some variety of sexual deviant. Rosenberg responded with chagrin, or a few times, hid his face behind a sheet of music. He also occasionally acted in comedy bits, during or after which O'Brien nearly always ridiculed Rosenberg's meager line reading and acting skills.