I’ve just started re-reading Neverwhere. When Richard and Door first meet — after her injury has started to heal, anyway — he introduces himself as "Richard. Richard Mayhew. Dick," A page or two later, Door calls him "Richardrichardmayhewdick."

IIRC Neil Gaiman said he stole the joke from Douglas Adams, who had someone refer to "Dentarthurdent" in one of the Hitchhiker’s Guide to the Galaxy books, but I always think of a Charlie’s Angels episode in which someone greeted "Bosleyjohnbosley."

The thing is, I barely remember Charlie’s Angels, so the way I remember it is actually as "Bosleytombosley" … and in my memory, she’s saying it to Tom Bosley!