In no special order:

To Have And Have Not - Howard Hawks
Some Came Running - Vincente Minnelli
Vertigo - Alfred Hitchcock
The Naked Spur - Anthony Mann
Accattone - Pier Paolo Pasolini
Le Trou - Jacques Becker
Il Posto - Ermanno Olmi
The Leopard - Luchino Visconti
Citizen Kane - Orson Welles
Fox And His Friends - Rainer Werner Fassbinder
The River - Jean Renoir
Germany Year Zero - Roberto Rossellini
Ugetsu - Kenji Mizoguchi
Celine And Julie Go Boating - Jacques Rivette
8 1/2 - Federico Fellini
The Searchers - John Ford
The General - Buster Keaton & Clyde Bruckman
You Only Live Once - Fritz Lang
Spirit Of The Beehive - Victor Erice
Gun Fury - Joseph H. Lewis

I tried to limit it to just one movie per director. Otherwise it could've been all Hawks and Fassbinder movies. But what's the fun in that? Also, I left off Charlie Chaplin and Robert Bresson because I couldn't even begin to figure out which of their movies I liked best.