"When Pigs Fly" Similar idioms for impossible situations in other languages, according to some internets: "When chickens have teeth" (French) "When frogs grow hair" (Spanish) "When the cow coughs" (Portuguese) "When the owl's tail blossoms" (Latvian) "At horses' easter" (Romanian) "When the crayfish whistles on the mountain" (Russian) "When the 7-11 is closed" (Thai) (really?) "Tuesday" (Fridaynish)

one Thanks to Donna for suggesting I use this