For only the second time since 1937 when Supporting Actor/Actress awards were first given, the top 6 awards of Best Picture, Actor, Actress, Supporting Actor, Supporting Actress and Director went to 6 different movies (the first time this happened was 1953). The six films in 1957 were respectively Around the World in 80 Days (1956), The King and I (1956), Anastasia (1956), Lust for Life (1956), Written on the Wind (1956) and Giant (1956). This will not happen again for 49 years. However, if you extend the list to include writing, and rank Best Screenplay - Original above Best Screenplay - Adaptation (this was the first year the writing awards were so named), then 1957 gives the top 7 awards to 7 different movies (The Red Balloon (1956)) and this certainly is unique.
1957 was the last year in which the Academy Awards would be bi-coastal, with ceremonies in both Hollywood and New York. Since 1958, the ceremony has been exclusively in Hollywood, and East Coast viewers have come into work yawning the next day, ever since.