The actual movie script is intentionally visible in three different scenes.
Captain Carter's "belly button" was a screw-cap from a toilet, an idea put forth by Will Edwards.
Director Chris Gabriel's dog, Rufus, not only appears in a sequence in the movie intentionally, he also made a cameo in one of the officer's club scene. Rufus had to be allowed to stay on set to keep him from crying outside. His tail is visible under the table at one point. This shot was left in the movie in honor of cheap 1950's special effects, like wires showing on space craft.
In the opening sequence the jeep is seen driving off into the distance. At the end of this scene, Henry Clarke got the jeep stuck up to its axles in the soft, drifting sands. It took two hours to dig it out and the help of a motorcyclist who went and picked up an old pallet and brought it back to the production team.
Originally, Captain Mason was a sergeant, but it helped the story more that he was an officer. He then became a lieutenant, but writer Chris Gabriel got tired of writing "lieutenant" and didn't want to abbreviate in the script.