An event or series of events where you get feeling that people are watching you or even trying to alter your thoughts or actions in accordance to their script. The term comes from the 1998 movie, The Truman Show. Especially true when brought on by an occurrence similar to one in the movie itself.
SeaBass: Dude, I just had a Truman Show moment!
SquirrelMaster: How's that?
SeaBass: I was driving in my car, and on the radio they started talking about our small town, and they never do that!
SquirrelMaster: Maybe you should get that checked out.
SeaBass: My radio?
SquirrelMaster: No, your head...