Here are a couple of others to throw in the competition. "Visitors" is the one that was popularized by Whitley Strieber in his best-seller Communion. "Others" is what Richard Dolan and I called them in our book A.D. After Disclosure. Our take was that they weren't us and we couldn't be 100% certain who they actually were. They were simply Others. That's the one I use these days most often.