Playing Against Type: Kurt Russell as David's psychiatrist. He has mentioned taking the role deliberately for this reason.
Romance on the Set: Tom Cruise and Penelope Cruz started dating after working together in this movie. Although it is said that one of the main reasons why Cruise wanted to make the remake in the first place (apart from because he really liked the original Spanish movie) it's because he got infatuated with Cruz after watching Open Your Eyes.
Throw It In: The line "I'll tell you in another life, when we are both cats" was something Penelope Cruz said to Cameron Crowe in a moment of frustration. He loved it so much he made it a key part of the movie.