Odd factoid about Family Guy creator Seth MacFarlane: he had a ticket on Flight 11 out of Boston on the morning of 9/11. He was late for the flight.
Wikipedia has details, and MacFarlane also refers to it at the very end of this interview with the Onion’s AV Club:
The Onion: You were scheduled to travel on one of the planes used in the 9/11 attacks. Did the fact that you were nearly part of it affect how you viewed the subsequent fallout?
SM: Not especially. I’m not a fatalist… What I felt more than anything else was gratitude toward my travel agent for screwing up my itinerary.