It's bloody hard to stop this thread from being derailed by one or two people, especially one, which is very unfortunate as we live in a vale of tears and could do with a good laugh, or even a groan.

So here's a rejigged one, courtesy of the great Barry Cryer. Laugh or groan at will:

Knock knock

Who's there?

Queen Elizabeth

STOP THE FUNERAL!

I'll get me coat...