One of the novel "weapons" that appeared in the movie Despicable Me was the fart gun. Basically a gun capable of unleashing the sound and smell of flatus.
A toy version of this was released in conjunction with the film, though this version only made the appropriate range of sounds. The Good Doctors managed to obtain one of these toys on the October 4, 2013 show, and its use was liberally sprinkled throughout the show for a few weeks.
Remember, there is no such thing as a cheap laugh. And as Mark's Scooby Doo anecdote illustrates, sometimes what you really need to get you through the day is a funny fart.