I was in a research lab at work when a guy who worked down the hall stuck his head in and said that a plane had hit the WTC. He was kind of a loud mouth jokester whose jokes were seldom funny, so I wasn't quite sure I should believe him. Walked down to the plant cafeteria where there was always a TV on, saw the gathering crowd, and knew it was for real. Watched for awhile, then asked for the day off, called the wife and told her to take the day off, (she worked for a quasi-govermental agency) went back to the cafeteria and saw the second plane hit, and then went home. On the way home, we each picked up a couple flats of water, (in case things escalated) and got home in time to see the Pentagon get hit.
Later we heard about passengers on FLT 93 heroically stopping the terrorists's plans for the fourth plane.
I will never forget.