I have a /lot/ of references in my world and campaign, but not the funny type, more the obscure reference-type that my players will never, ever get, but I find fun to put in. Almost all the names of places come from strange foreign languages, meaning something that actually makes sense, but only if you know a lot more about the world than the PC's are ever going to discover. And some references only make sense in relation to others and to things I personally associate in my head.