Here's my earlier post in which I solicited input on the funniest joke ever. Some of the submitted jokes were pretty good. Here's an article about the connection between laughing and lying (via GeekPress who asks "are you a good liar?" and Marginal Revolution where Alex Tabarrok says he's a lousy liar) in which the authors performed a study to find the funniest joke ever.
My favorite: What's brown and sticky?