One of my favorite movie techniques is the use of split screens. This is where there is a physical split in camera point of view and the camera is pointed at one thing on the right side and something else on the left. Or in some cases, different angles of the same object.

Brian DePalma has used it numerous times in most of films. For example, in Sisters, we have a sequence where a murder is being covered up on one side of the screen and then on the other we have a witness explaining to the police what she saw. Which leads into a complicated escape that uses the split screen to it's full advantage. During Carrie's prom night killing spree, the split screen allows us to see what's happening in more than one spot in the gym.

I was wondering if we could start a list of movies that have this technique being used. Here are the movies that I know of:

DePalma films:

Sisters (the murder cleanup sequence)
Phantom of the Paradise (the bomb sequence)
Carrie (the prom killing sequence)
Dressed to Kill (the stalking sequence)
Blow Out (the sound recording sequence)
Femme Fatale (used during numerous sequences)

Others:

Boogie Nights (emphasizing the aspects of Dirk's rise to fame and fortune)