http://en.wikipedia.org/wiki/Wellerism
Wellerisms, named after Sam Weller in Charles Dickens‘s The Pickwick Papers, make fun of established proverbs by showing that they are wrong in certain situations, often when taken literally. In this sense, wellerisms that include proverbs are a type of anti-proverb. Typically a Wellerism consists of three parts: a proverb or saying, a speaker, and an often humorously literal explanation.
My favourite: “Much noise and little wool,” said the Devil when he sheared a pig.”