Pull my finger

Pull my finger is a joke or prank regarding flatulence in which a mark is asked to pull the finger of the joker, who simultaneously farts so as to suggest a causal relationship between the two events.

A comparable activity is attributed to a character in a short story by Mordecai Richler (collected in The Street, 1969):

A variation on this joke appears in Yasujirō Ozu's film Good Morning (1959). Schoolboys ask each other to push their foreheads, responding with an expulsion of gas.

In 2008, an iPhone app from Air-O-Matic called Pull My Finger was one of the most popular apps in Apple's App Store, purchased over 50,000 times in less than one week. It allowed users to pull a virtual finger, activating the sound. The phrase is now the focus of a legal battle between Pull My Finger and InfoMedia's iFart Mobile app over the use of the phrase.

In 2015, an MRI study of how knuckles trigger popping sounds was jokingly called the "pull my finger study."

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