Trivia: Throughout the show, the number 47 appears many times. There are multiple room 47's (where Syd found the Circumference in season 1 and the room in her memories from season 3, among others.), there are 47 Rambaldi artifacts, and Page 47 of the Rambaldi manuscript was the page that had Sydney's picture on it. Also the pagers flash 47911 when they get called into the office.
Trivia: At the end of the episode, Superman believes that Lex Luthor died after giving the Anti-Life Equation to Darkseid, who also vanished along with Lex while the others believe that Lex is still alive, and they might see him again. According to Dwayne McDuffie, Lex Luthor and Darkseid became a permanent part of the source wall when they solved the Anti-Life Equation. The same fate that happens to anybody who solves it.
Trivia: Lou Diamond Phillips made two appearances on the show, as Mark DeSalvo, the security chief where Victor Drazen is being held. Philips and star Kiefer Sutherland are known for having worked together in Young Guns and Young Guns 2.
Trivia: The name of Byers' father is Bertram. In The X Files episode, "The Unusual Suspects," Byers tells the police that his name is John Fitzgerald Byers, born on 11/22/63, and that before JFK's assassination, his parents were going to name him Bertram.
Trivia: "Foot Chalet" is a combination of Sports Chalet and Foot Locker.