Once Upon a Time in the West (1968) http://movieclips.com/QjNJr-once-upon-a-time-in-the-west-movie-harmonicas-flashback/ Frank: Keep your lovin' brother happy. --- In Cold Blood (1967) http://movieclips.com/Jfhi-in-cold-blood-movie-the-last-living-thing-youre-ever-gonna-see/ Dick: What are you sore about? We got no beef. It's us against them. Perry: This is between us. It's got nothing to do with them. Perry's Father: Look at me boy! Take a good look! Cause I'm the last living thing you're ever gonna see! Here's the classic "crying window" scene where Perry tells the story of his father saying those words to him. An explanation of sorts what was going through Perry's mind that night and why we see the flashback before the murders. Perry's line "This is between us. It's got nothing to do with them." takes on a whole new meaning thanks to a great use of flashback: http://movieclips.com/vqnJa-in-cold-blood-movie-hopeless-dreams/

i think it'd be also helpful to see the setup that leads to the flashback.. this one is from Scrubs/so not film but they do a lot of these and they always work, so I thought it'd be a good example Dr. Cox: How's that leukemia patient of yours doing? J.D.: I'm hiding. I don't really want to be bald. I have a sneaking suspicion that it won't work for me. I think it would accentuate my spoon chest [touches his chest] Dr. Cox: Yeah [nods approvingly] J.D.: Plus, the girl I'm dating is totally into my hair. Dr. Cox: She's gotta be interested in more than you hair. ***FLASHBACK*** THE BAR Tamara: If it weren't for your hair, I don't think I'd be remotely interested in you. ***BACK TO PRESENT*** J.D.: I'm sure there's something else she's into. ***FANTASY/FLASHBACK*** THE BAR Tamara: No, there's nothing else. ***BACK TO REALITY*** J.D.: There is...even if she won't admit it. You know what, I'm stuck, man. I have to shave this down. [points to his hair]

Butterfly Effect is a good one that has a bunch.

Airplane The Bar Scene http://bit.ly/xdNa5M Ted Striker: "It was a rough place, the seediest dive on the wharf. Populated with every reject and cutthroat from Bombay to Calcutta. It was worse than Detroit."

@Jeff - Brilliant clip! For myself, I would like to put forward for following: Chasing Amy - Finger cuffs Scene http://www.youtube.com/watch?v=cxWRWbdsTjc Cohee Lundin: [Explaining how Alyssa's High-School nickname "Finger-Cuffs" came to be] Alyssa Jones? Shit I know Alyssa Jones, I mean I KNOW Alyssa Jones! Know what I'm sayin'? Me and Rick Darris used to hang around her house after school and shit cause her parents were like never home and shit. One day Rick just whips it out and starts rubbin it on her leg and shit, starts chasin her around the living room. I was dyin. But you know what the crazy bitch did? She drops to her knees and she just starts suckin him off. Right there in front of me, like I wasn't even there man. I almost died. But that's not the fucked up part. The fucked up part was Rick, man, right in the middle of it, he turns to me and he says 'Cohee!' Just like that, 'Co-Hee!' So I'm like, "Yo ill give it a shot." So I start pullin' her pants down and shit. All slow cause I'm figurin' any minute she's gonna turn around and belt me in the mouth and shit right? But yo check this shit out man. Shes all into it. She doesn't even try to stop me or nothin'. Shes all wet and shit and I just start going to work, Know what I'm sayin? Me and Rick are just going to town on this crazy bitch and shes just loving it, all moaning and shit, it was fucked up! So Ricks the one that came up with the nickname, cause that day she had us locked in tight from both ends like a pair of god-damned Chinese finger cuffs!

Shawshank