And where is Pulp Fiction ? Clockwork Orange ?

How is it that Pulp Fiction didn't make the list!

Rocky Horror and Pulp Fiction - hands down!!

My own favorites, some cultish, some less so, but I will watch them everytime I stumble upon them:
Rocky Horror -- the best
Hedwig & the Angry Inch
Caddyshack
Animal House
Blue Velvet
Labyrinth
Stripes
Valley Girl
Breakfast Club
Last American Virgin
Fast Times at Ridgemont High
Young Frankenstein
Blazing Saddles
Robin Hood Men in Tights
Holy Grail and every Python film and episode ever made

A couple more

Being John Malkovich
Memento

In Memento the scenes are in backwards order.  The protagonist's wife has been killed and he's trying to figure out what happened.  And he keeps losing his memory after short periods of remembering so he has to make reminders for himself.  Hard on the head but pretty well done. 

I'm a fan of a number of the movies mentioned here -- Harold & Maude, The Adventures of Buckaroo Banzai Across the 8th Dimension, Repo Man, Monty Python and the Holy Grail, The In-Laws (original), Brazil, Blue Velvet. 

A few other cult films not listed:

The Adventures of Priscilla, Queen of the Desert
Angel Heart
Five Deadly Venoms
The Gods Must Be Crazy
The Harder They Come
Heathers
Heavy Metal
Reefer Madness
The Room
Scarface
The Toxic Avenger

Angel Heart creeped me out real good.  Heavy Metal was great the first time I saw it.  I thought Scarface had some good shock value, but ended up as an ultraviolent cartoon.   

David Lynch with Laura Harring and Naomi Watts 

'You know, being a director of really weird films is not such a bad gig.'

Dune and Highlander.

 Donnie Darko

Its gotta be Rock and Roll High School. Come on, Ramones, PJ Soles and of course Clint Howard. The definition of great cult movie!

Notable omissions:  Holy Grail, Pulp Fiction, The Road Warrior.

"The Goonies" ?  Please - I don't think so.

In Response to Re: Your favorite cult movie?:

i con cur

  American Psycho ---there is no question

Labrynth, I guess.
Unless Dr. Strangelove counts.

Pulp Fiction

Fargo

The Jerk

Take The Money And Run (Woody Allen)

I would expect:

  A Clockwork Orange
  Monty Python and The Holy Grail
  A Christmas story (maybe)
  Dr. Strangelove

I agree with Rocky Horror being the best cult classic.
Love the interactive show in Cambridge.
My favorite would have to be "Logan's Run" from 1976.

The Crow

Count me in for Repo Man. It's hilarious.

I love the Repo Man's Code.

'I shall not cause harm to any vehicle nor the personal contents thereof, nor through inaction let the personal contents thereof come to harm' It's what I call the Repo Code, kid!"

"It helps if you dress like a detective. Detectives dress kinda square. If you look like a detective people are gonna think you’re packing something."

Who did Lost Highway?  Quite bizzare, but intriguing.  Perhaps I was younger, but I got a good kick out of how the main character is answering the phone at the beginning, and the movie returned to the same scene at the end with him making the call. 

Talking to yourself without knowing it is an odd play on Fugue's, and possible given that the plot slopped forwards and backwards through time.  Non-linear allright.

There was only one Anime / Animated film listed:
Akira is overrated as an anime film. It's too crowded a plot to really enjoy. Most people love it for the bike fight sequences in the beginning.

Ghost in the Shell - Focused on the subject of personality - are we just a box of images and memories, or is there a divine spark that makes us special: a "ghost" inside us. Inspired a sequel and two spin-off prequel TV series.

Ghost in the Shell 2: Innocence - Focused on illusion versus reality. If reality can be completely simulated, then how do we know what is "real"? Set several years after the events in the first movie.

Cowboy Bebop: The Movie - The crew of the Bebop must stop a soldier-turned-terrorist who has a score to settle.  A must-see for the opening "Ask DNA" animated music video by Seatbelts in the beginning. 

Honorable  mention:

Death Race 2000 - Vehicular homicide is America's new national sport in a future decadent police state. Death Race was a gritty remake without the cultural and political satire. One of Sylvester Stallone's first movies.  

Forbidden Zone - Starring jugglers-turned-New-Wave-band  'The Knights of the Ancient Order of Oingo-Boingo', guest-starring future composer Danny Elfman (the brother of the band's founder and a key member) as Satan. A colorized version is now available on DVD.

The Hidden - Kyle McLachlan plays a weird FBI agent following a violent fugitive and Michael Nouri plays an LAPD detective assigned to help him. The two must join forces to stop an apparent sleeper cell of psychotic spree-killers posing as ordinary law-abiding citizens. 

Metalstorm: The Destruction of Jared Syn -So good they made it in stunning 3-D.

Mister Mike's Mondo Video Show - See Dan Ackroyd's webbed toes! Written by the former first head writer for Saturday Night Live. Has several of SNL's "not-ready-for-prime-time-players" in cameo roles.

Night of the Comet - Red dust from a near-Earth comet's trail turns exposed humans into violent mutants.

Nomads - The plot is told in psychic flashbacks experienced by a female ER doctor after she treats a mortally-wounded man just before his death. The deceased (played by Pierce Brosnan), was a restless French anthropologist specializing in nomadic cultures. Adam Ant and his friends are urban nomads he tries to study.  

Outland - High Noon in space. Stars Sean Connery as a US marshall at a mining colony trying to shut down a drug ring ('nuff said).

Scanners - People turned into psychic mutants by an experimental drug try to take over humanity. 

Seven Black Notes (AKA "The Psychic") - A model whose mother was brutallly murdered has vivid dreams about her mother's death. Considered one the best of the Italian "Giallo" horror films. The main motif from the film was used in Kill Bill I when The Bride waits behind the door to ambush Buck. 

She - This version from the 1980s starring Sandahl Bergmann has little to do with the H. Rider Haggard novel. Describing it is like a Stephon sketch from SNL: "It has everything... Amazon warriors, mutant mummies with Raybans and chainsaws, a gauntlet of purity...

Warriors of the Wasteland - Stars Patrick Swazey as a wasteland barbarian.

Repo Man
Wild At Heart
Blue Velvet
Rivers Edge
Big Lebowski
Rude Boy

It's not number one by any means and probably shouldn't have even made the list, but I personally like Heathers.

Monty Python
Caddyshack