Well, 666 isn't scary right NOW. But it could be later...
My lucky seat, believe it or not, is 13A. In any plane type, any airline. All of the times I fly in seat 13A, I have a good flight. SURE, it's just dumb coincidence. But it's kinda something funny to joke about. So, for my upcoming TWA flights (I mean, AA connecting in STL) I booked on 13A!!!