This thread will probably die on its arse, but here goes. What are peoples favourite characters that appeared once and once only in a sitcom?
Mine has to be Jed Maxwell from I'm Alan Partridge, the deranged stalker with a scary room filled with Partridge memorabilia... In fact, Partridge is one of the best shows for truly memorable one off characters. In that same first series, we also meet Kevin Eldon's Laughing Yet Racist Hotel Guest, who laughs at everything and anything, then complains about their being two many blacks. Back of the net!
One of my other favourites is the Deaf Old Woman from Fawlty Towers, who prompts Basil to do his classic spiel about Torquay and herds of sweeping wilderbeest.