A partial shortlist below:
Humphrey Bogart Casablanca (1942)
"I think this is the beginning of a beautiful friendship"
Renee Zellweger Jerry Maguire (1996)
"You had me at hello"
Clarke Gable Gone with the Wind (1939)
"Frankly my dear, I don't give a damn"
Arnold Schwarzenegger Terminator II (1992)
"Hasta la vista, baby"
Gloria Swanson Sunset Boulevard (1950)
"I'm ready for my close-up"
But what makes these lines so memorable? Researchers at Cornell University think they have 'created a computer program to break down the formula behind some of cinema's most enduring lines'.
Hasn't this 'formula' alway been the elusive holy grail for Hollywood? Disney hired top screenwriters for their epic John Carter - only to end up with one of the most expensive flops of all time. In contrast Casablanca was famously chaotic in its development, with actors going into celebrated scenes with hastily rewritten scripts.
As William Goldman pointed out in his seminal 'Adventures in the Screen Trade' the formula will always remain out of reach because 'nobody knows anything'.
More on Cornell research