I don't cry when watching movies with people, but when I'm watching them alone I'll pretty much weep at anything. Aside from a lot of the ones already mentioned here, some that always get to me are:
The Fall
A Little Princess
The Piano
Crash
The Fountain
Little Women
Pan's Labyrinth and the Orphanage. (only got slightly teary watching Mama). Damn Guillermo making me feel things. Pacific Rim better not make me cry.
Oh man and these two.