The Sicilian scene in True Romance featuring Christopher Walken and Dennis Hopper is movie perfection. When Hopper understands his fate, look out. What followed was the the greatest dialogue in movie history I believe. Just perfect.Including Tarantino movies in this topic really isn't fair to everyone else. Just set those aside for the sake of continuing the thread.
Goodfellas has quite a few. The Fargo restaurant scene. Legend has a couple, like the bar fight scene.
De Niro and Pacino in Heat.
Most underrated movie of all time.
Underrated scene: Damon and Turturro in the bath house in Rounders
Also, the final scene in The Hustler between Newman and George C. Scott with Jackie Gleason listening...so good.
I recently read that tarantino was responsible for some of the dialog in Crimson Tide.I am absolutely partial to all things Tarantino. Here is a trailer for a great movie NOT written by him that is killer if you enjoy dialogue driven thrillers. It is the time honored plot of a bunch of tough guys locked in a room and have to figure something out. It is as if you took Twelve Angry Men/Glengarry Glen Ross and mixed it with Reservoir Dogs. I highly recommend this movie if you haven't seen or heard of it.
He also wrote the original Natural Born Killers. Oliver Stone rewrote so much stuff in it that Tarantino totally dissolved himself from the movie. There is a scene in the movie where there is a Mexican standoff outside a store. Pretty sure Tarantino wrote that scene.I recently read that tarantino was responsible for some of the dialog in Crimson Tide.