Background: London rhyming slang. Named after J. Arthur Rank, a twentieth century British film producer.
NOUN: Masturbation, or Wank. Rank provding the requisite rhyme.
NOTE: Besides the obvious rhyme origin, this piece of slang may come from the famous opening of Rank's films, which depicted a muscular man in a Toga banging a gong.
"Carmen Electra is so hot, I give myself a J. Arthur every time she's on TV."