The Wilhelm scream was recorded for the film Distant Drums (1951). You can hear the scream in a scene where a man is bitten by an alligator. Years later this sound effect was called 'Wilhelm', named after the character Pvt. Wilhelm from The Charge at Feather River (1953). Since then the Wilhelm scream has been used in hundreds of films.
In which movie do you least expect to hear the Wilhelm scream? You may discuss the list here