Alternative Character Interpretation: Obviously with Trent, like if he's a fictional character within another fictional story or just a guy who's mentally insane and little to none of the movie actually happens.
Hilarious in Hindsight: In this movie, a Stephen King expy reveals that his novels are just him channeling the wishes of an eldritch being. A decade later, the real King wrote himself into his Dark Tower series, claiming that his novels are just him channeling the wishes of an eldritch being.
In this case, it's less than Hilarious In Hindsight and more an Homage to this film, since Carpenter and King tend to feed off each other's work.
David Warner plays a shrink who evaluates Sam Neill's character, which is interesting considering both actors were part of The Omen trilogy (which like this film also had an apocalypse theme). Ironically, Warner had played the ill-fated photographer and The Lancer Keith Jennings in The Omen (1976), while Neill had played the adult Damien Thorn in The Final Conflict.
Memetic Mutation: The "Did I ever tell you my favorite color is blue" scene is a minor meme on the net.
One-Scene Wonder: Jürgen Prochnow and Charlton Heston, both of whom have only a few minutes of screen time. David Warner and John Glover may also qualify.