Thanks! I will admit that I had to look up the origin... while I had seen They Live! back when it was new, I most recently heard the quote revised from an episode of The IT Crowd. I knew that they had taken it from somewhere, but I hadn't taken the time to look it up until now. It's just too great a quote to not use it whenever possible. (I never played Duke Nukem 3D, but I'm aware it was also used there.)