The motorcycle Dean remarks on was improvised by Jensen Ackles.
Mary introduces herself as Shirley Partridge, with Sam and Dean as (David) Cassidy and (Danny) Bonaduce. All members of the 1970's TV musical sitcom The Partridge Family.
Ruth Connell, who plays Rowena, is actually 15 years younger than Mark Sheppard, who plays her son, Crowley - the King of Hell.
While most movies and TV shows have made up addresses, the address of 1781 Chamberlain Lane is only partially made up. Chamberlain Lane does exist in Maplewood (Ramsey County), Minnesota, but the addresses start in the 3000s. Also, when Sam says that he is in the "St. Paul Police" database, that would be in keeping with the numbering system for St. Paul if there was a "Chamberlain Lane" in St. Paul.
Nikolai Witschl, who plays the Coroner in this episode, also plays doctor/coroner Dr Curdle on another CW show, "Riverdale."