The Academy of Motion Picture Arts and Sciences has put together a beautiful animated video with posters from some of the films from the early 20th century to present that have won the Academy Award for Best Picture.

"The King's Speech" (2010):

"Rocky" (1976):

"The Bridge on the River Kwai" (1957):

"One Flew Over the Cuckoo's Nest" (1975):

Via Tjock (SE).