General

All studio ghibli movies

Disappearance of Haruhi Suzumiya
Can't wait to watch The Disappearance of Yuki Nagato

@SilverFoxR: Always the way , there's loads of quality movies that get forgotten
Just checking a few lists online

Toyko godfathers is meant to be good
so is 5cm per second and the girl who leapt through time

The Ghost in a shell movies are very good

Memories - 3 shorter segmented movies , all very good , as is The Animatrix

Vampire hunter D - very good

Appleseed is meant to be good

Tekkon Kinkreet looks good and is highly rated

The final fantasy movies, whilst not anime , they are very good , the spirits within is great , and advent children is awesome

The Iron Giant and Titan AE are both awesome

The wolf brigade is meant to be good

Fullmetal Alchemist: The Sacred Star of Milos is very good too

Like you say though I get the feeling something is missing from the list, it'll come back to use then just post it here

The Animatrix , Memories and Metropolis are probably the best in my opinion, worth checking out in the very least

5 centimeters per second
Colorful

[quote=osmund]Yer Trigun: Badlands rumble is very good,

Redline is very good

The Animatrix is very good[/quote]

Ohsh... I completely forgot Redline! I KNEW I was missing one and now I'm kicking myself for forgetting what is probably my all-time favourite anime movie!

Hotarubi no Mori e and The Girl Who Leapt Through Time. Didn't really get the praise for Summer Wars, since it was basically a remake of Digimon: Our War Game.

Garden of Words. Animation as real as it gets.
@yumtoast I would like your opinion on it.

Howl's Moving Castle
Kiki's Delivery Service

Garzeys Wing, the dub is so hilariously bad. <3

Yer Trigun: Badlands rumble is very good,

Redline is very good

The Animatrix is very good

Everyone has mentioned Summer Wars and Wolf Children, but before both of those movies, they did another very good anime movie, "The Girl Who Leapt Through Time". You should absolutely check it out as it has an equally odd and cool set-up.

But yeah... as most people have said, the Cowboy Bebop Movie, Summer Wars and anything by Studio Ghibli are great. Other movies I'd probably suggest are:
-Trigun: Badlands Rumble (not amazing, but still a fun addition to the series)
-Any of the Slayers movies (some are episode-length, some are full movies, all are great)

id have to say Akira but i do love all the studio ghibli movies

Has to be Spirited Away. I don't even remember what it's about. All I know is I saw it 8 years ago and that it was my first taste of anime. I thought it was the best thing ever.

Cowboy bebop knocking on heavens door
One piece movie Z

Rebuild of Evangelion <3
I like most of the Ghibli Movies esp. Howl's moving castle

I like all the studio ghibli movies and Detective Conan ones.

Summer Wars, I'm completely in love with the animation. <3

wolf children and graveyard of the fireflies, you like being depressed I see

Spirited away as people have said is very good

Cowboy bebop movie and the bleach movies!

I really liked the Evangelion movies , the animation is awesome in them

Sword of the Stranger is very good too

The One Piece movies are quality too

I've read Hal is meant to be quite good

Metropolis the animated movie !

I say any movie made by Hayao Miyazaki

I much prefer series over movies, but my favorite is either Kara no Kyoukai series or 5 Centimeters per Second.

definitely spirited away

Spirited Away is my all time favorite anime movie.

I also liked Akira and Full Metal Alchemist : Conquerors of Shamballa

Spirited Away captured my heart since the beginning

No favorites, but I did enjoy Hotarubi no Mori e and Eve no Jikan.

I've been hearing good things about the AnoHana movie, so I'll be watching that soon, considering the BD has been around for 2 months.