https://www.youtube.com/watch?v=aqp43JghkMQ
Paul Rudd stopped by Letterman, surely to promote something but also to shower the retiring host with a little bit of praise. His method? Showing that he was once a member of the David Letterman fan club back in the 1980’s (that period when Letterman was a maverick force in late night comedy). The Royals were in the playoffs, Young Paul Rudd was probably hanging out with Young Joe Buck, and there was a fan club devoted to the cult of Letterman.
The problem was that the fan club was apparently not official. NBC and Letterman were forced to sue the unauthorized club, but Rudd had already gotten his official club button and official club dehydrated sponge (that’s what that is called, I assume). He brought both to the show and shared a moment with Dave when they both dipped the club sponge in water for the first time.
(Via The Late Show)