Telethon (or Charity Anthem) was a game played on the American edition of Whose Line, and once in the very last British episode.
Featuring all four performers, the game would begin with the audience naming an unlikely group to benefit from a telethon ("NBA Players" and "Sitcom Stars" being two). Ryan Stiles and Colin Mochrie would then perform as the hosts of the telethon urging people to donate to the charity in question. The game would then progress to a musical stage, during which Wayne Brady and Brad Sherwood would perform an anthem for the telethon as different musicians. In most playings, Ryan and Colin would introduce new musicians in the course of the song, generally playing to the singers' strengths (other times, Brad and Wayne would apparently choose their impersonations on their own). Brad, for example, would be asked to perform as Bruce Springsteen or "The guy from the B-52s", with Wayne doing impressions of Prince, Stevie Wonder and Bill Cosby.