Once took off on the dispersal at Ubari airport in southern Libya, in about 100m, but the wind was 20G30kts on the nose and we were light. The earlier landing with said wind fully crosswind was considerably more exciting.
Tower's response to my request was nothing more than 'clear take off'. Not sure he fully understood, thinking back...
Narrowest was CSH5 Saint Ferdinand in Canada, also on an epic slope.
Fly safe, have fun, Sam.