Personally I'm not a believer in UFOs piloted by aliens from another world, UFOs from this world yes. I've seen two things in the sky in my life, one had an explanation the other has several plausible explanations.
The first time I saw the Stealth Bomber, at a Vandenberg Air Show it was coming in straight on and it looked like a flying disk. It took a few seconds for my mind to accept what my eyes were seeing and even after it flew directly overhead it looked like a flying protractor. I could see how someone seeing it during its testing phase could mistake it for something otherworldly.
The second time I saw something odd was in Belize. A group of us had wrapped up a nine day dig on a Mayan city and had been partying in the evening. I decided I was tired of partying, had only had a couple of beers (the beer there is terrible) and went on the roof to lie down and take in all the stars as I live in a city and don't see a lot of stars due to ambient light. I was staring at a particular grouping of stars for several minutes when of a sudden one of the "stars" suddenly took off at a very rapid rate of speed and disappeared off in the horizon. I suppose it could have been a meteor coming straight on until it hit the atmosphere then veered off or a satellite but it hadn't moved for quit a while while I was staring at it. That one may be unexplainable.
Anyone have an opinion on UFOs or any experiences that defy explanation? Let us know what you think about the UFO phenomenon and let's please keep it free of flaming.