Movies spend entirely too much time on alien fish-out-of-water stories, and not enough time on how the extraterrestrial visitors got here. NO MORE. Today we pay tribute to the coolest shots of alien landings, both the amazingly good and the "so good it's bad."

Why do we step inside the dreams of science-fiction heroes so often? We're already in the future, or on an alien world, so why take an extra leap into the world of the unreal? Here are some theories.