Here's a list of some of the lesser known mob movies.I found it floating somewhere on the net
WARNING-LONG POST AHEAD :p

Underworld 1927 Groundbreaking crime film follows a gangster fighting to stay on top in the Chicago underworld. This riveting silent film set the style for many gangster pictures that came after. Cast: George Bancroft, Evelyn Brent.
Scarface 1932 Loosely based on the life of Al Capone, this is the gangster movie that set the standard in the '30's, with wonderfully id-driven performance by Muni, countered equally by Raft as his rival. Cast: Paul Muni, Boris Karloff
Baby Face Harrington 1935 A timid straight arrow is mistaken for a mobster, which gets him in hot water with both the real Mob and the cops. Cast: Charles Butterworth, Una Merkel.
Angels With Dirty Faces 1938 Cagney and O'Brien play buddies from a tough New York neighborhood who grow up on opposite sides of the law. One becomes a murdering gangster, the other a priest trying to keep the local kids from emulating the life of crime. Cast: James Cagney, Pat O'Brien, Humphrey Bogart.
Angels Wash Their Faces 1939 Sequel to Angels with Dirty Faces, this time with a D.A.'s son trying to clear a gang member of false arson charges. Cast: Ann Sheridan, Dead End Kids.
White Heat 1949 Consumed by his relationship with his mother, a psychopathic mobster is brought down by a relentless government agent. Well-done gangland film loaded with violence. Cast James Cagney, Virginia Mayo.
The Mob 1951 A hard-nosed cop infiltrates the Mob in order to bust their illegal dockyard activities. Crawford is an ideal tough guy, and the stellar supporting cast adds a touch of class to the proceedings. Cast: Broderick Crawford, Ernest Borg nine.
Machine Gun Kelly 1958 Bronson has an edgy intensity as famous gangster in quick-moving action picture. Cast: Charles Bronson, Susan Cabot.
Al Capone 1959 Uncompromising, often gritty documentary-style biography about the rise and fall of notorious Chicago gangster Al Capone during Prohibition. Cast: Rod Steiger, Fay Spain.
Murder Inc. 1960 A couple falls into trouble with a powerful crime syndicate and can't get free of its murderous grip. Gritty, fact-based story with Falk turning in a compelling performance as a notorious contract killer. Cast: Peter Falk, Stuart Whitman.
Underworld USA 1960 The Mob and the FBI are at war, and a loner out to avenge his father's brutal murder gets caught in the middle. Violent but visually effective piece. Cast: Cliff Robertson, Dolores Dorn.
The Rise and Fall of Legs Diamond 1960 Fast, clever and ultimately poignant story of slick killer Diamond, a man incapable of giving love, but very good at dealing with death. Cast: Ray Danton, Karen Steele.
Mad Dog Coll 1961 Polished but forgettable gangster biography follows career of insanely vicious mobster. Cast: Telly Savalas, Vincent Gardenia.
Accattone 1961 Gritty tale of criminal underworld follows a small-time hood trying to come to terms with the directions his life has taken. Cast: Franco Citti, Franca Pasut.
The Scarface Mob 1962 Brisk, satisfying gangster yarn of Eliot Ness vs. Al Capone. Originally the pilot for The Untouchables TV series. Cast: Robert Stack, Barbara Nichols.
The St. Valentine's Day Massacre 1967 Bullets fly and bodies pile up in umpteenth version of famed 20's gangland massacre. Lots of violence. Cast: George Segal, Jason Robards, Frank Silvera.
The Brotherhood 1968 Tale of generational conflict within the Mafia, can't avoid comparisons with The Godfather, released four years later. Cast: Kirk Douglas, Alex Cord.
The French Connection 1971 Tough renegade New York cop and partner uncover the trail of a massive overseas heroin ring. Cast: Gene Hackman, Roy Shrieder.
The Valachi Papers 1972 Notorious gangster turns informer on the Mob, Violent film version of Peter Maas' fact-based bestseller about the Mafia. Cast: Charles Bronson, Lino Ventura.
Across 110th Street 1972 What’s the biggest mistake a Harlem street gang can make? Stealing $300,000 from the Mafia. Quinn is a racist police captain caught in the middle of the resulting bloodbath. Fast moving and violent with a capitol V. Cast: Anthony Quinn, Yaphet Kotto.
Honor Thy Father 1973 Life on the inside of the Mob, based on Gay Talese book about the life of Joseph Bonanno and his son. Cast: Joseph Bologna, Raf Vallone.
The Sicilian Connection 1974 Lurid, dangerous dealings of a band of notorious opium traders. A lot of excitement and relentless action. Cast: Ben Gazzara, Silvia Monti.
The Outfit 1974 Duvall is professional thief forced out of retirement by Mafia hit on his brother in terrific cast of old film noir habitués, crisp direction, and terse and cool performances by Duvall, Baker. Cast: Robert Duvall, Joe Don Baker.
The French Connection II 1975 In this sequel, New York cop pursues heroin kingpin all the way to Marseille, but is soon addicted to drug himself. Cast: Gene Hackman, Fernando Rey
Capone 1975 Slick exploration biography follows the rise and fall of legendary Chicago mobster Al Capone. Emphasis is on action and atmosphere. Cast: Ben Gazzara, Susan Blakely.
Bugsy Malone 1976 A truly original movie: A spoof of '30s gangster movies, done as an all-kiddy musical. It's bizzare, silly, and fun. Cast: Scott Baio, Jodie Foster.
Scarface 1983
Mafia Princess 1986 Autobiography of Antoinette Giancana, daughter of long-time Chicago Mafia boss. Curtis gives one of his best performances as Sam Giancana, aging 40 years over the course of the movie. Cast: Tony Curtis, Susan Lucci.
The Sicilian 1987 Ponderous, confusing chronicle of Salvatore Giuliano, who took money from Italy's Big Three-the Church, the State, and the Mob- to fund Sicily's secession from mother Italy. Cast: Christopher Lambert, Terence Stamp.
Married to the Mob 1988 The widow of a mob hitman wants to leave the Family, but the mob chief has eyes for her. Cast: Michelle Pfeiffer, Alec Baldwin.
Nitti: The Enforcer 1988 TV film fictionalizes the life of Frank Nitti, Al Capone's right-hand man. Very bloody and violent. Cast: Anthony LaPaglia, Vincent Guastaferro.
Capone 1989 Dismal recap of famed gangster's life. Cast: Ray Sharkey, Keith Carradine.
Hit List 1989 A vengeful family man goes after the cold-blooded Mafia killer who's abducted his son. Cast: Jan-Michael Vincent, Leo Rossi.

State of Grace 1990 Irish police officer returns to New York to confront some old friends gone bad. This type of ethnic character drama, spiced with gangster violence, has been done much better, but explosive performances help mask story weaknesses. Cast: Sean Penn, Ed Harris
Mobsters 1991 Slater, Dempsey, Grieco, and Mandylor portray real-life mobster Lucky Luciano, Meyer Lansky, Frank Costello, and Bugsy Siegel, looking more like kids dressed in their father's old suits. Cast: Christian Slater, Richard Grieco.
Bugsy 1991 Marvelously elegant portrait of star struck gangster Bugsy Siegel and his passionate affair with actress Virginia Hill, as well as his vision for cheating Las Vegas. Cast: Warren Beatty, Annette Bening.
Billy Bathgate 1991 In the '30s, a streetwise kid works his way into the organization of Dutch Shultz. But the vicious Mob life isn't the escape from poverty he expects. Highly polished, handsome, yet somehow less than-compelling drama, dominated by Hoffman's strong performance. Cast: Dustin Hoffmann, Nicole Kidman.
Reservoir Dogs 1992 Impressive debut by writer/director Tarantino. Witty, violent ensemble piece about conflict among thieves after aborted jewel robbery. Violence is extremely graphic and may be upsetting to some losers. Cast: Harvey Keitel, Tim Roth.
Hit the Dutchman 1992 Interesting gangster epic about the Mob war in NYC that led to the assassination of Dutch Shultz. Cast: Bruce Nozick, Eddie Bowz.
Carlito's Way 1993
Amongst Friends 1993 Friends' loyal connections are put to the test when their gang turns to crime. Stylistic flourishes give a sleek look to an otherwise age-old tale. Cast: Steve Parlavecchio, Joseph Lindsey.
Flight of the Innocent 1994 Mafia feud in Sicily causes young boy to flee with his pursuers hot on his trail. Cast: Manuel Colao, Francesca Neri.
Federal Hill1994
Kiss of Death 1995 Cast: David Caruso, Nicolas Cage.
Casino 1995
Brooklyn State of Mind 1996 Cast: Vincent Spano, Danny Aiello.
Hoodlum 1997
Gotti 1997
In the Shadows

This Thing of Ours 2003

The Boss of Bosses

The Godfather Tales

The Last Don II 1998

there is also a movie called Made

I keep meaning to rent that. Is it any good?

i havn't watched it i just saw it in a shop

http://home.wanadoo.nl/marcelboven/Start.html

Just press on 'Misdaadfilms' on the left (in the menu).
It's a dutch site, but with many mob(gangster)movies

now does anyone actually have all these movies or most of them I got like 11 right now

i haven't seen the movie but i was wonderin how is kill bill a gangster movie? LLC said had it on his list a while back and i was j/w

I don't think you want every single gangster movie ever made, as a good portion of em aren't worth the film they're printed on. Gigli anyone?? [/b][/quote]Very true, sir! There are SOO MANY crap Gangster flicks its ridiculous. Just shoot for the good ones.

The key to getting the good films is buy the Mobster films. Gangster films aren't good, but Mobster films are great. Scarface is an exception to this rule.

I usually just shoot for ones that have a good story to tell,and have good actors/directors.Other than that,I get them for target practice.

'the long good friday' and 'the krays' are definitely the best british gangster flicks ever i recommend them to anyone who hasn't seen a british gangster movie.