9. R2D2
Hang on, you mean R2 wasn't a real, fully-working robot? This is basically like a magician showing you the false door in his Mystical Closet. Thinking back to Star Wars, I'm not even entirely sure why there was any real need to have an actor inside the body of the little robot: he doesn't exactly have human-like dexterity or movement, and his shots could surely have been achieved through the used of effects and model work. Just seems unnecessarily cruel to subject anyone to that sort of heat.