I saw one in 1992 in West Texas along I-10. It was a flat black cube much larger than a jumbo jet at about 5,000 feet and it never budged an inch in any direction. I actually pulled over and watched it for about ten minutes, then had to continue my journey. It remained in place until I had traveled out of sight.
When I was a boy in Memphis, Tennessee, I lived in an area where there were no street lights and on a clear night the sky would almost be white with stars. This was also at the time of the paranoia about nuclear war happening at any moment. And in that time and place it was normal for all of the neighborhood kids to play outside at night until about bedtime (10 PM or so). Anyway, me and some of my friends would lie on our backs at night and watch the sky - we often saw formations of triangular shaped flying objects that were visible only because they blocked out the starlight - they were not airplanes as in that era every boy over 6 could quote you chapter and verse on every airplane or car in operation on sight and at night too. These objects never made any sound and never had any flying lights. We suspected some sort of Russian bombers with invisibility capability - I guess its because we expected anything we could not identify to be a Russian bomber only moments away from vaporizing us all. We did have the major Naval aviation base at Millington, Tennessee about 10 miles North of us and it was on the prime target list for a Soviet nuclear strike. We knew what we were seeng wasn't Naval aircraft; I am 100% certain these were legitimate UFOs.