The producers of the low-budget indie science fiction film "Moon" wanted computer-generated effects to create the lunar vistas and futuristic vehicles seen in their film, but budget restraints severely limited their options. Luckily for them, they had veteran model-maker Bill Pearson on hand. To create the rovers and the moon base, Pearson, who got his start supervising the model effects for Ridley Scott's "Alien" (1979), used a dense foam sheet called Foamex -- thin enough to cut with a scalpel -- for the walls. The lunar surface was constructed on a 40-foot-by-24-foot platform raised 3 feet off the floor with the rovers dragged along it with a fine tungsten wire. The lunar sand was made from kitty litter. "It became lumpy when the rover drove over it," he said. "It was a great detail. A lucky accident, I would call it."