BS”D
WD-40, which is very familiar to anyone who has ever eaten fried food in a yeshiva or seminary dining room, stands for Water Displacement Formula #40. It took the manufacturer 40 tries to come up with the right formula, and then they distributed it via the US Army in soldiers’ rifle packs during the Vietnam War. When the servicemen came back, they used it around the house, on sports equipment etc and then somewhere along the line a Vietnam War vet who was sentenced to community service and forced to cook in a yeshiva kitchen after he vandalized a shul used it to fry latkes on Chanukah.
Someone in said yeshiva’s hanhala tasted the latkes and decided they were perfect to make sure bochurim would not concentrate on gashmius and WD-40 became the standard cooking oil used (and reused) in yeshiva and sem kitchens.
And one part of this story is true and the other one is not….. :))))!