List1 of 9
1. "Sisterhood of the Traveling Pants"
Obviously this is the first one on the must-watch list, and for good reason. This movie basically put Blake Lively on the map -- you know, pre-"Gossip Girl." The entire cast just couldn't be better, and it really hits home when you can compare it to the important female friendships in your own life. Plus, they're in Greece, duh.