Trivia: Hammond doesn't appear in the second book (though he does in the second movie). This is because, in the book series, Hammond was killed in the first book. He slipped, broke his ankle and was fatally attacked by compies.
Trivia: At the dinner ceremony where Spawn attacks Wynn and kills Church, you can see a red-headed woman in a blue gown walking among the patrons in the beginning of the scene. The camera focuses on her briefly, but for a reason - look at her earrings. They are Spawn insignia. This is a reference to the angel Hellspawn hunter Angela, who wears those same insignia in the comics as trophies of her victories over previous Hellspawn. Very clever reference.
Trivia: The view that people acquired citizenship and the right to vote through military service reflected the views of "Starship Troopers" author Robert Heinlein. His views were influenced by his years in military service during World War II, and what he saw as the supposed "laziness" of civilians.
Trivia: In the scene where Carrey is in the stretcher at the airport, if you look in the back of the crowd to the right, you will see Fire Marshall Bill from In Living Color. He can be seen when Carrey's ex-wife is speaking to the officer speaking on a walkie-talkie. (01:16:11)
Trivia: In the last scene where Dunn, is watching the TV in the store window and he looks over and says to the guy standing next to him, "Hey, you look just like that guy", it is actually his stunt double.
Trivia: When we see Paul in the van as it is taken over by the overflowing river, just as he hits the water, we hear the Wilhelm scream.
Trivia: All the characters in the movie are named after famous prisons around the world - Holloway, Wren, Leavenworth, San Quentin, etc. The characters match the prison types too - Alderson never meets the group, and isolation is the major form of punishment at Alderson Prison in West Virginia. Dr. Holloway is a female doctor, and Holloway Prison is a women's prison in England, Kazan is autistic, and Kazan Prison is Russia is a "disorganized" prison, etc.
Trivia: After Teri Hatcher's character has been murdered, James Bond (Pierce Brosnan) shoots dead her killer (Vincent Schiavelli). When he does so, the expended bullet cartridge ejects very, very quickly and hits Brosnan squarely on the forehead.
Trivia: In the beginning of the movie, when Rayden 'shoots himself' against Kahn, he makes a strange cry, which is actually from the Mortal Kombat II games.
Trivia: The lava was primarily made of methylcellulose, the thickening agent used in fast-food milkshakes, and the ash was made mostly of ground newspaper.
Trivia: Because of their roles in the film, both Brad Pitt and David Thewlis were banned from entering China.
Trivia: Capitan Gonza's head looks just like the crone Yubaba's green bouncing head pets in director Hayao Miyazaki's 2001 film "Spirited Away."
Trivia: The collector who calls Banky a tracer is played by film producer Scott Mosier.
Trivia: During the beginning of the film, Al Pacino and Keanu Reeves are on top of the office building. Pacino is promising money, clients, and power to Reeves if he joins his firm. This is a reference to the temptation of Christ where Satan took him to a mountain and showed him all the cities of the world and promised it to him if he bowed down to him.
Trivia: As already noted, Hercules wears a lionskin which is made out of Scar. In the myths of Hercules one of his great tasks was to kill a vicious lions and he kept the skin ever since. But it's more than just a joke or a cameo that he wears Scar, for both Scar and Hercules were animated by the same man (Andreas Deja).
Trivia: The voiceover radio broadcast at the end of the movie is spoken by Roger Moore - the original Saint from the TV series.
Trivia: Many of the corridors in the Event Horizon are coffin shaped - perhaps foreshadowing the fact that it is a "death" ship?