I want to take this moment to speak on something that really bugs the hell out of me. And that is UFO's - or rather the people that see them and have to seem apologetic or worried that people will think they are a freak for even remotely thinking the strange thing they are seeing is a UFO.
U.F.O. is an acronym for UNIDENTIFIED FLYING OBJECT. That's it. It doesnt mean that it's a space ship from another planet!
If you look up in the sky and see something flying and cant tell what the hell it is, then guess what? You just saw a UFO. Call it a UFO. Tell all your friends that you just saw a UFO and dont feel the need to tip-toe around the concept or pre-apologize so people dont think you're a loon that might believe in aliens visiting our planet.
I'm not discounting the possibility of aliens visiting our planet or whatever at all. And that gets to the heart of this concept. People should stop worrying about imagining things out to all ends. That's how we figure stuff out and learn. You see something you dont understand so you start constructing and imagining concepts about what it is, etc and then we rule them out and study it until we figure out what it is and why. So having the possibility of it being an alien spacecraft is certainly within the boundaries of things the UFO could be and shouldnt be discounted simply because some people think it's too sci-fi.