My pal, Penney, once told me that when she was a kid, and her family went on vacation, they would "drop the spoon" every afternoon. I knew this was a cousin of the disco nap, but I never knew it was a purported invention of Salvador Dalí, (according to QuestionSwap):

Lie down or sit in comfy seat holding a spoon in your fingertips. you should be holding it in a way that - when you loose consciousness (sleep) you drop it... the Clatter (put a big plate on the floor under your hand) will wake you.... and you get woken JUST as you enter the best "dreamy" bit of your sleep.

Related (though pretty insane, if you're asking me) is the notorious "Thomas Edison Nap," which, repeated through the day, is intended to stand in lieu of an actual solid night's sleep (and which seems to have partly inspired some of the polyphasic sleep nutjobs proponents). Edison is said to have naturally needed less sleep in a day, and seldom slept very much in a given stretch, claiming that excessive sleep was a sign of laziness -- and yet: