Mensa retest
The Mensa retest, a test that purportedly verifies the eligibility of a Mensan for continued membership, has sometimes been referred to humorously within Mensa in response to a Mensan doing something allegedly showing sub-Mensan intelligence. Sometimes it is used as self-deprecating humor by Mensans commenting on their own less-intelligent actions. Abbie Salny has given a popular talk on "Dumb Things Smart People Do" at many Mensa gatherings, but did not conduct retests even while she was the Supervisory Psychologist of American and International Mensa; no such thing has ever existed. Qualifying for Mensa, by internal testing or outside evidence, lasts for life, no matter how much your brain may have deteriorated since!
The Creative Mischief SIG posted signs at Mensa gatherings in the 1990s reporting the postponement of this test, to the relief of those who questioned their own ability to pass.