My personal favorite line was in "Donnie Brasco," which was during the fugazi diamond ring situation. That was when Pacino said "How the fuck do you know that's a fugazi? You only looked at it for two fucking seconds." Below are some other funny ones. Please fill free to put more.

Richard Castellano
"Leave the gun, grab the cannolis" - The Godfather

Armond Assante
"You know what you both should do? You both should become CPA's. Yeah certified public assholes, this way you can have your blue shield and workers comp. On top of that you go pay your taxes" - Gotti

Unknown actor
"If she goes down on the old br$$$ knowing that the guy in the truck was watchin' then she's a whore and she can't be trusted" - A Bronx Tale

Joe Pesci
Funny how? You mean I make you laugh, I'm here to fuckin' amuse you? Tell me what the fuck is so funny about me" - Goodfellas

Don't know if My Cousin Vinny is considered a mob flick, but one quote that always makes me laugh is Marissa Tomei to Joe Pesci, "Oh yea, and you Blend!"


TIS

Tony Montana: Why don't you try sticking your head up your ass? See if it fits.


Uncle Jr. :I got feds so far up my ass, I can taste Brylcream."

Great Ones. What about Bobby Bacala telling Tony at the restaurant about the backs of notre dame. He said u got your quarter back, half back and hunch back of notre dame.

An earlier Sopranos episode had Bobby Bacala and Vito Spatafore talking and their big bellies were almost touching...Paulie Walnuts then quips; "They look like their in a weight loss commercial - before and waaaaay before!"
That one wakes me up in the middle of the night laughing!

I liked the one in Sopranos where Carm confronts Tony about his Russian mistress and warns him not to get her pregnant, nor to bring home any venerial diseases from her. "I had her tested for AIDS!" Tony shouts. "What kind of a guy do you think I am???" My sister called it "twisted male logic."

There is great run of dialog between DeNiro and Keitel in "Mean Streets" in the back room of Tony's bar: "Is she da one on my left...or on your left?" And, "Joey Scal." "Yeah, I know him." "An' Joey Clams." "Yeah, I know him, too." "No, no: Joey Scal is Joey Clams..."

From Goodfellas:

After Sonny gave Tommy the $7,000 bar tab.
Tommy: "Ya wanna laugh? This prick asked me to christen his kid. I charged him $7,000."


Paulie: "Tomorrow we gotta eat sangwiches." (I love the way he mispronounces the word 'sandwich.')

From Godfather:
Vito mocking Johnny Fontaine: "Ooooh, what can I do?"

Clemenza to Michael: "Why dontcha tell that nice girl you love her? I love ya with alla my heart. If I don'ta see youa soon, I'ma gonna die."


From Donnie Brasco:

When Sonny took Lefty into the pitch black room before giving Lefty the lion as a gift

Lefty's reaction: "I think I shit my pants."
Sonny: "Whaddaya think? You was gonna get whacked?"

My favorite scene, from my favorite Scorsese film. According to Scorsese's bio, by Roger Ebert, the scene was very much ad-libbed by Keitel and DeNiro. Keitel says he felt DeNiro was giving him a little "Abbott and Costello," kind of tongue-in-cheek, so Keitel decided to run with it.

DeNiro has great "straight man" comic ability. Who would've known?

"Analyze That," the dreadful sequel to the great "Analyze This," had one gut-busting moment. DeNiro is with a hooker in Billy Crystal's guest bedroom and they're making all kinds of, er, noise. Well, Billy calls DeNiro into the foyer and says, "Paul, I have a 17 year old son in the house!," to which DeNiro replies, "I'll ask her," with a dead serious expression on his face .

Hysterical.

Good line PB. But "dreadful" to describe Analayze That is the least of descriptions of it.

Tony Soprano taunting Uncle Junior at the golf course after he finds out that his uncle gives head to his girlfriend.

"South of the border, down Mexico way."
"Uncle Junior's in the muff. Oh, I'm sorry did I say muff?"

You forgot about this great line from casino.
" You took your boots off? You put your feet on the table... you shit- kicking, stinky, horse-manure-smellin' motherfucker you!"

Sopranos:
Fin telling Meadow about Vito's advances:
" I think he wants to kill me....or fuck me....or kill me then fuck me...I don't know...."

Donnie Brasco:
Not really a line but when Donnie takes his wallet out to spot Lefty a twenty and Left grabs his wallet, takes the cash out ..." whassa Donnie....a wiseguy don't use no wallet....you carry it like this...." and left puts it in his pocket and walks on. Same with the Xmas card scene later on.