Heh, and I was almost about to say that I was surprised that nobody had mentioned "Leon" yet...

Leon, The Iron Giant, and The Green Mile are definites.

Evelyn
Cinema Paradiso
Stand by me
About a boy

Another vote for Grave of the Fireflies. If this one doesn't get you, you must have faulty tear-ducts.

http://images.amazon.com/images/P/B0...1.LZZZZZZZ.jpg

Tess (Polanski)
Nights of Cabiria (Fellini)
Juliet of the Spirits (Fellini)
Los Olvidados (Bunuel)
The Best Years of Our Lives
Groundhog Day (I don't know why)
For Whom the Bell Tolls
So Proudly We Hail
The Childhood of Maxim Gorky
Forbidden Games
The Umbrellas of Cherbourg
Dark Victory
The Sullivans (also known as The Fighting Sullivans)
Toy Story 2 (The Doll's Song)
Titanic
A.I.
Contact (the preview audience I saw it with lost it completely during the "For Carl" dedication final title)
Marie Antoinette (continuously during the last 15 minutes, both the Norma Shearer and Michèle Morgan versions)
The Pumpkin Eater (Anne Bancroft losing it at Harrod's)
La Strada (Fellini) (very final scene)
The Spiral Staircase (final scene)
Johnny Belinda
The Iron Giant
West Side Story (Robert Wise) (final scene)
Helen of Troy (Robert Wise) (if you're young and in love)
Une Vie (after Maupassant, by Alexandre Astruc, with Maria Schell)
A Star is Born (George Cukor)
Sunrise (Murnau) (15 minutes in)
I remember Mama (death of Uncle Kris)
8 1/2 (Fellini) (last scene)
Spartacus
How the West Was Won
(when you see them the first time: )
Gone With the Wind
It's a Wonderful Life


... Three of those films star Giulietta Masina , four are by her husband Federico Fellini(!).

The Shawshank Redemption does it to me every time...the ending of Big Fish will get most people...some people (myself included) can resist Dances With Wolves, Good Will Hunting, and Gladiator, but if you don't shed a tear when Optimus Prime dies in Transformers: The Movie, you have no soul.