This one’s almost a no-brainer, but the recent discussion reminded of it:
You are paranoid. You find threats everywhere, and believe many of them to be linked in a conspiracy against you. This may cause you to shy from dangers that don’t actually exist, distrust others who actually have your best interests at heart and believe things are much more complicated than they actually are. Yet you may also predict true dangers that others aren’t aware of, or see through complex knots of plot to the true nature of things.
Many — most? — PCs probably have at least a rating of 1 in Paranoid, but it could be fun to highlight it in play.