"The Princess Bride" is one of the best movies ever. To call it stupid is just, well, stupid!  Im concerned about your taste, Chy.

Lets see: (a short list)

 - The Stand

 - What Dreams May Come

 - Scarface

 - 300

 - Evil Dead

 - The Breakfast Club

             well, that'll get me started anyway...

this is spinal tap, fubar, super bad, pulp fiction, and the warriors for sure

MAP:Ahahahaha!My taste!I'm actually worried about yours.

Well I just know a whole bunch of movies,hardly of any I can remember...but they were good lol

Bladerunner ..how could I forget that one  one of my all time favorites
also Outlaw Josey Wales.
Of Mice And Men
and SlingBlade

Someone mentioned This Is Spinal Tap, hehe... That's a great mockumentary...

As for more decent rockumentaries.. How can

The Doors (with Val Kilmer as Jim Morrisson)
Almost Famous

ever be beaten?

More in the fantasy genre: Conan the Barbarian! That's a classic... The soundtrack to it may be better than the movie itself though. Hehehe...

..and:
2001: A Space Odyssey (2010 wasn't bad either)
A Clockwork Orange
Bram Stoker's Dracula (w/ Gary Oldman)
Blood for Dracula (aka Andy Warhol's Dracula, w/ Udo Kier)

are absolutely great movies.

did I forget Akira!
Audition
Old boy
Les tontons flingueurs
Music wise
The last Waltz
Let there be rock

The Matrix trilogy

The Alien quadrilogy! Given that the first two are the best, the third is the most claustrophobic, and the last one is just for laughts!

Anyone mention these yet:

Apocalypse Now
Hamburger Hill
Platoon

from Germany:

Lola Rennt
Goodbye, Lenin!
Der Untergang
and the Must Have Memorized Front To Back: : : : DAS BOOT

I loved Topsy Turvey too ................. G&S great stuff

fish

Seven Samurai and pretty much anything by Kurasawa.
Bladerunner, yeah.
Excalibur too.
Also
Children of paradise
Spirited away and Paprika for the anime stuff
Topsy Turvy was a great look at the theatrical life and had some great G&S music.
Waiting for Guffman, Best in show, Spinal tap and A mighty wind. Great ensemble cast and funny as hell.
A guilty pleasure for me is Robocop. Silly but cool.

LOTR,
Transformers, 
Alice in Wonderland
Yes Apocalypse Now too

well, theres soo many.

LOTR (amazing and brilliantly done)

matrix (1st one, because the idea itself was just out of this world)

jurrassic park 1 (cos it was the first film ever with SFX that made you poo ur pants)

city of god

watership down, lion king, dark crystal, fifth ellement (not necesarally the best but childhood favourites)

studio ghibli stuff
anything tim burton has a role in is usually good
some of tarrintinos stuff
the indiana jones tril
and of course the star wars stuff (everything except ja ja bloody binks)...

Nightmare Before Christmas
Edward Scissor Hands
Corpse Bride
Dante's Peak
Office Space

Well, there's a lot of movies that qualify for "great", and it's great to see how many great titles are showing up in this thread!

Here's two older movies that certainly need to be on this list:

Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964, a black comedy about nuclear war w/ Petter Sellers, by Stanley Kubrick)

Tora! Tora! Tora! (US/Japanese co-production 1970, about the attack on Pearl Harbor, showing both sides of the story) I certainly prefer this one over the more recent movie about that historic event.

Lord of the Rings
Dark Crystal
Dune
Harry Potter
Excalibur
Dances with Wolfs
Star Wars
Finding Nemo
Dinosaur
Matrix