I'm actually glad to find a semi-intellectual thread in this forum, since I'm really into movies.
First of all, I'd like to point out that I like Scorsese too. The Departed, for example, is one of few movies you can call flawless in every way, and it was a great exciting, yet not at all cliché movie in general.
Quentin Tarantino is a must on my list. Even though his Pulp Fiction got a lot of praise, I think Reservoir Dogs is really his best one yet. I am a big fan of dialogue, and the way the story evolves, and how those trivial everyday conversations are geniously mixed up with what happens is just amazing. I love the irony in his work too. One famous example would be the "Stuck in the Middle"-scene from Reservoir Dogs. Also a great movie is Four Rooms, in which Tim Roth (Mr. Orange from RD and Dr. Cal Lightman from recent tv show Lie To Me) plays the protagonist who has to check on four rooms in the course of the night. The final room's part is written and directed by Tarantino (and acted in!), and you can really tell. The end is just brilliant and actually hilarious, but not in an obvious way.
Another director would be Stanley Kubrick. I simply adore what he has done with A Clockwork Orange, and it is among my top 5 movies ever. David Cronenberg is the director from Eastern Promises and A History of Violence. Excellent movies, with some hard to shoot scenes, but really great results. And yes, Spielberg is one of the masters. Even for Saving Private Ryan alone should he be admired in eternity. Not to mention Munich, another one of my favourite movies. The Brothers d'Ardenne: Belgian twins who have won the Golden Palm two times (I think) for their hard, realistic, sober films about the everyday but poor life in the southern part of Belgium. Another one that comes to mind is David Fincher. I have yet to see Fight Club, but the rest of his movies are great, especially The Game and Zodiac.
There really are many-many more, but these are the ones I have seen more than one movie of.
P.S. The Thomas P. Anderson guy. Is that the one from Magnolia? Cause I really liked that one. Lots of psychology and dialogue.
P.P.S. I am really good at remembering names when it comes to movies, but I have really seen too much of too many different styles to think of my favourite movies at the moment. So I'm just listing the directors that come to mind.
There are too many great movies that don't have famous directors too. Too many...
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