Here's a few :

The Wind will Carry Us by Abbas Kiarostami

8 1/2 by Frederico Fellini (though this might be a bit much
                            for some beginner's)

L'Atalante by Jean Vigo 

Kadosh by Amos Gitai

Three Colors Trilogy by K. Kieslowski

Wild Strawberries by Ingmar Bergman

A Short film about Love by K. Kieslowski (or all of the 
                                          Dekalog)

Salaam Bombay by Mira Nair

Yomimibo By Akira Kurosawa 

Bangkok Dangerous by the Pang Brothers

Viva L'Amour by Tsai Ming-Liang

Stanlingrad by Joseph Vilsmaier

Behind the Sun by Walter Salles

Vengeance is Mine by Imammura Shohei

Red Cherry by Zhang Li

Amores Perros by Alejandro G. Inarritu

Woman in the Dunes by Hiroshi Teshigahara 

Open your Eyes by Alejandro Amenabar

Zero Kelvin by Stellan Skarsqard

Madadayo by Akira Kurosawa

Dersu Uzala by Akira Kurosawa

Tin Drum by Volker Schlondorff (though this one might be 
                                be a bit much for some 
                                beginners)

The Merchant of Four Seasons by Rainer Werner Fassbinder

The Great Silence by Sergio Gorbucci Spaghetti Western

Diabolique by Henri George Clouzot

The Seventh Seal by Ignmar Bergman 

Wooden Man's Bride by Jianxin Huang

High and Low by Akira Kurosawa

The Tree of Wooden Clogs by Ermanno Olmi (one of the best
                                          movies I've ever
                                          seen) 

The Obscure Object of Desire by Luis Bunuel

Dairy of a Chamber Maid by Luis Bunuel

Belle De Jour by Luis Bunuel

The Road Home by Zhang Yimou (Had me crying like a baby)

Ordet by Carl Theodor Dreyer (might be a bit much for some 
                              beginners)

Das Boot by Wolfgang Petersen (possibly the best war movie
                               ever)

Aquire the Wrath of God by Herzog (though mentioned, can't 
                                   be mentioned enough)

Repulsion by Roman Polanski

Sonatine by Kitano Takeshi 

Killer by Darezhan Omirbaev

Human Condition Trilogy by Masaki Kobayashi 

Eureka by Shinji Aoyama

Ali Fear Eats the Soul by Rainer Werner Fassbiner

Audition by Takashi Miike (might be a tad scary for some)

The Sacrifice by Andrei Tarkovsky (might be a tad slow for 
                                   some)

Come and See by Elem Klimov

Barking dogs never bite by Joon-ho Bong

In the Mood for Love by Wong Kar-Wai

Plenty more, but that's a good start.

                                          