I just saw AoD the other night. Very funny movie. I noticed that even though I had never seen the movie before, I have heard almost every line that Ash says somewhere else before.
Is this the most quotable movie ever made?
“Your only leading two things right now- Jack and Shit. And Jack just left town…” My favorite. 
AoD is great, but I think Ghostbusters or Princess Bride is more quoted/quotable.
“Nimble little minx, isn’t she?”
“Back off man, I’m a scientist!”
“You don’t look good. You didn’t use to look like this”
Fenris
I’d vote for Withnail and I as the most quotable.
“As a youth I used to weep in butcher’s shops.”
“I mean to have you, boy, even if it must be burglary.”
“I must have something’s flesh!”
“I feel unusual.”
“We want the finest wines available to humanity, we want them here, and we want them now!”
“Come on lads, let’s get home, the sky’s beginning to bruise, night must fall and we shall be forced to camp.”
Army of Darkness may seem familiar if you’ve played a lot of Duke Nukem 3D. A number of the lines were incorporated into the game.
At least ones of the lines was lifted from the previous movie in the series, Evil Dead 2: Ash’s use of “Groovy.”
Hmmm…in my circle it’s always Spinal Tap that gets quoted.
“It’s such a fine line between stupid and clever”
“You can’t really dust for vomit”
“How much more black could this be? And the answer is none. None more black.”
“Two words: Shit sandwich.”
“These go to eleven.”
“That’s just nitpicking isn’t it?”
A lot of these quotes you have to really know in the context of the movie, plus you’re required to put on your best faux Briton accent for full effect.
Oh MAN. I quote Spinal Tap all the time. I try to work “I’m just as God made me” into any situation I can.
Whereas I think Army of Darkness is the greatest movie ever made (I own about five different copies of it), and it has some of the most memorable silly quotes ever, I regretfully have to say that Austin Powers is the most quoted movie in recent times. I mean, how many times have you carried on a conversation with a group of 10-30 year olds and someone doesn’t shout "Yeah Baby!’ or “Oh, Behave” or some other like shit.
GOD I fucking hate that movie.
I seriously doubt Army of Darkness even makes the top ten. Number 1 would be “Monty Python Live at the Hollywood Bowl,” since it contains several classic Monty Python routines, and Python is massively quotable.
I’d wonder if Casablanca enters into the running (assuming you count misquotes)
“Play it again, Sam” and “This looks like the start of a beautiful friendship” are among the movie’s classic lines.
And I don’t think I’ve ever been in a conversation where someone has thrown out an Austin Powers quote. Thank god.
Daniel
In my family, the quoted movie of choice is Fletch.
“What, do you need a refresher course? It’s all ball-bearings these days!”
“Dr., uh, Rosen Rosen”
“Manure-spreader jack-knifed up on the interstate”
“Moon-River!”
“You using the whole fist there doc?”
Animal House, hands down.
I don’t know about most quoted, but Fletch and Fletch Lives are certainly my favorite to quote from:
[Fletch is being interrogated by Chief Karlin and is giving him attitude]
Chief Karlin: What’s your name?
Fletch: Fletch.
Chief Karlin: What’s your full name?
Fletch: Fletch F. Fletch.
Doc: That’s an interesting name, Mr…?
Fletch: Babar.
Doc: Is that with one B or two?
Fletch: One. B-A-B-A-R.
Doc: That’s two.
Fletch: Yeah, but not right next to each other, that’s what I thought you meant.
Doc: Isn’t there a children’s book about an elephant named Babar.
Fletch: Ha, ha, ha. I wouldn’t know. I don’t have any.
Doc: No children?
Fletch: No elephant books.
Receptionist: Can I help you Dr.–?
Fletch: Oh it’s me, Dr. Rosenpenis. I’m just here to check out Alan Stanwyk’s file.
Receptionist: Dr. who?
Fletch: Dr. Rosenrosen, i’m here to get into the records room.
Receptionist: What was that name again?
I’d have to list “Army of Darkness” and “Big Trouble In Little China” as the top two quotable movies of all time. I’ve collected about 20 favorites each at: http://tnmc.homestead.com/Q20armyofdarkness.html
“I’ll swallow your soul!!” … “Come get some.”…TRM
Another vote for The Princess Bride as the most quotable movie ever. As a TPB quote-file once quipped, “Note that this file does not include every notable quote from the movie, as that would require reproducing the entire script.” 
In my group of friends, it’s Groundhog Day…again.
Ned Ryerson: Phil? Phil Conners? I thought that was you! Now don’t say you don’t remember me, because I sure as heckfire remember you!
Phil, to the groundhog: Don’t drive angry. Don’t drive angry!
Phil: I’m a god. I’m not the God. I don’t think.
Phil: Do you ever have deja vu, Mrs. Lancaster?
Mrs. Lancaster: I don’t think so, but I could check with the kitchen.
Mrs. Lancaster: Will you be checking out today, Mr. Conners?
Phil: Chance of departure…eighty percent. Seventy-five, eighty.
Phil: Do you want to throw up here, or in the car?
Ralph: I think…both.
Phil: Too early for flapjacks?
Phil: Well, what if there is no tomorrow? There wasn’t one today!
Phil: No white chocolate, no fudge.
Rita: What are you doing? Are you making some kind of a list? Did you call up my friends and ask them what I liked?
Classic stuff.
Every other line in “Casablanca” seems to have entered popular usage.
“I stick my neck out for no one.”
“Round up the usual suspects.”
“Play it again, Sam.” (Yes, I KNOW this is a misquote)
“I am SHOCKED to find there is gambling going on here.”
“Louis, this looks like the beginning of a beautiful friendship.”
“We’ll always have Paris.”
“Here’s looking at you, kid.”
The list goes on. I don’t think ANY other movie is quoted as often.
I think Monty Python and the Holy Grail make up about 85% of all movie line quotes. Which is a big reason why I am sick to death of this movie. I’ve given up Python quotes entirely, and now, when in need of a cinematically-themed quip, I quote exclusively from My Dinner with Andre.
Lets not forget Apocalypse Now. There is the little matter of charlie’s inability at water sports, and the affection for certain aromas in the morning air.
My friends and myself will go in cycles. Lately we have been quoting Glengarry Glen Ross all the time, although I doubt it would make a more general list.
“Get them to sign on the line which is dotted!”
“These leads are shit!”
“Coffe is for closers, only!”
“Fuck you! That’s my name!”
excuse me, I believe you have my stapler
Yeah…That’d be greeaat
PC Load Letter…what the #$@% does that mean?
Well, I wouldn’t say I’ve been MISSING it, Bob.
I don’t want to go to pound-me-in-the-ass prison
Um… yeahhh. Did you get the memo? Tell you what, I’ll just send along another copy, ok?
puttin’ on my “Oh!” face
And so on…
Anyone wanna second my nomination?