We just finished watching The Time Traveler's Wife.
Yeesh, I haven't cried that easily during a movie since I Am Sam. Rachel McAdams playing Clare was even better than I imagine when reading the book. She was so heartfelt and she made me cry so much! I read the book several years ago and forgot how bittersweet the entire book was, but especially the ending. I thought the film was a wonderful rendition of the book and exceeded my expectations with the special effects. Of course, I'm biased because I think Rachel McAdams is an adorable actress and I enjoy everything she's in. (Hello, She WAS the main character in The Notebook!)
The trailer for The Time Traveler's Wife shows all the best parts of the movie and fortunately doesn't make me too sad when I rewatch it!
If you like romantic movies with a dash of science fiction and don't mind a tearjerker, enjoy!