Butch Cassidy and the Sundance Kid  (1969)
Possibly the best Western film ever, it has surprisingly very little drinking in it.  But the tense tale of Butch and Sundance's final days culminating in one final, lopsided standoff will have you pouring more than one shot for yourself during its running time.  Robert Redford and Paul Newman create one of the best acting duos of all time.  If you haven't seen it, there's not a lot of sense in talking to you until you have.

Other Western options:
The Wild Bunch
High Noon
The Good, The Bad, and the Ugly
Casablanca  (1942)
Enough heartbreak and quiet pondering for seven films, Casablanca is a whiskey drinking extravaganza for the viewer.  If you've ever sat alone at a bar with a glass of bourbon and a cigarette, contemplating how and where things went wrong, Humphrey Bogart was way ahead of you, pal... 

Other Bogart options:
The Caine Mutiny
Treasure of the Sierra Madre
The Maltese Falcon
Chinatown  (1974)
Of many memorable characters he's given us, Jack Nicholson's Jake Gittes might rank as his most bourbon-inducing.  Full of piss and vinegar and self-confidence, Gittes unravels a Southern California mystery with a smoke and a snoot-full.

Other Nicholson options:
Five Easy Pieces
The Last Detail
Prizzi's Honor
Glengarry Glen Ross  (1992)
The film is a full-on "sausage party" with a nary a woman to be found (except for the Chinese hostess who takes coats) and features some of America's finest actors in one of the best ensemble films ever.  David Mamet's tense, desperate screenplay (based on his stageplay) crackles even more with a neat shot of Maker's Mark in your hand...so have one ready.

Other Mamet options:
House of Games
American Buffalo
Homicide
The Godfather parts I and II  (1972 and 1974)
Gangster flicks lend themselves to great bourbon enjoying for the viewer (with three making appearances on this list), and Francis Ford Coppola's epics are no exception.  The Corleone family's life of loyalty, betrayal, tragedy, joy, and violence is a perfect choice for a day (and I do mean a full day) of sipping your favorite bourbon.

Other Pacino options:
Heat
Dog Day Afternoon
GoodFellas  (1990)
I'm not sure there's a film I've seen more times than Scorsese's gangster tour-de-force (although Jaws would come close).  Featuring the best voice-over narraration in film history from Ray Liotta as Henry Hill, GoodFellas' frantic pace and violent, smoky presence makes a glass of your favorite whiskey nearly a must.

Other Scorsese options:
Taxi Driver
Raging Bull
Casino
Miller's Crossing  (1990)
Hampered by the unfortunate circumstance of coming out in tandem with Scorsese's GoodFellas, the Coen Brothers' highly underrated gangster gem is all snappy dialogue and tinking ice cubes in whiskey glasses.  Gabriel Byrne has never been better as he's surrounded by the scowering, glowering Jon Polito, John Turturro, and (who could forget?) Albert Finney.  The Danny Boy scene alone is worth a spot on this list!

Other Coen Bros. options:
Blood Simple
Fargo
The Man Who Wasn't There
Network  (1976)
William Holden, Robert Duvall, Peter Finch, and Faye Dunaway at the top of their game working with one of the best screenplays of all time (by Paddy Cheyefsky) all adds up to one of the best films ever made.  Ahead of its time in its message, the glut of shockingly insipid reality television on the airs now was already forecast in '76.

Other William Holden options:
Sunset Boulevard
Bridge on the River Kwai
Unforgiven  (1991)
Although a bit of "alcohol is evil" creeps into the screenplay, it's tough not to get excited when Eastwood's character begins pulling on the whiskey bottle before the final clash with Gene Hackman.  Morality and violence entangled in a Western tale?  Bartender, please!

Other Clint Eastwood options:
Dirty Harry
The Outlaw Josey Wales
A Fistful of Dollars
The Verdict  (1982)
Paul Newman is one of the finest American actors of my grandfather's time, my father's time, and my time and this is one of his showcase roles.  As ambulance-chasing, booze-swilling lawyer Frank Galvin, Newman has one last shot for redemption with a medical malpractice suit.  You'll take the journey with the heartbreaking character as you go sip-for-sip with him on his up and down ride.

Other Paul Newman options:
Hud
Cool Hand Luke
The Hustler  (this one may quickly subplant "The Verdict" on the list)