In this episode Clyde Bruckman is going through evidence trying to get psychic visions, and when he is holding a blue piece of cloth he says, "I got it! This is yours. This is from your New York Knicks t-shirt!" He was wrong, however in The X-Files: Beyond the Sea (1994) Luther Lee Boggs gets a psychic vision from a similar blue piece of cloth, and Mulder says "I tore this off my New York Knicks t-shirt. It has nothing to do with the crime."
There is a scene where Clyde Bruckman is playing cards with Scully. The camera briefly shows his cards - the two black aces and the ace of hearts, and the two black eights. That hand is a variation on the so-called Dead Man's Hand that Wild Bill Hickok was holding when he was shot in the back of the head in 1876 while playing poker. Four of the five cards in Hickok's hand were the two black aces and the two black eights.
The name of the character played by Peter Boyle is the same as that of the co-writer/co-director of the Buster Keaton silent classic, The General (1926). According to his IMDb filmography, the original Clyde Bruckman (1894-1955) was a prolific screen writer and director whose career spanned over 3 decades from 1919 onwards.
The trivia items below may give away important plot points.
This episode starts the legend among some fans that says Scully is not going to die, after Clyde Bruckman tells her she won't die. Later in The X-Files: Tithonus (1999), a man who cannot die exchanges Scully's death for his.
Pay close attention when Scully scans the crowds at the murder scenes. The killer appears in the crowd each time, except when the police are investigating the final psychic murder. In that scene, Scully is holding the tarot card picturing the bellhop as she pulls aside the curtain to scan the crowd, so even though the killer is absent, he is still represented in the shot.
The character Clyde Bruckman claims he got his abilities from thinking too much about a coin toss taking place between The Big Bopper Richardson and Ritchie Valens, which got Richardson his place next to Buddy Holly on the plane that crashed, causing both of their deaths. In fact, it was Valens, not Richardson (nor Allsup) who won his seat in a coin toss. Richardson got his seat because he had the flu due to the busted heating on the tour bus that lead to them chartering the plane in the first place.
Agent Scully's Pomeranian dog, "Queequeg", is named for the harpooner in "Moby Dick." There are some parallels with the dog and the person in Melville's book. a) Scully & Ishmael accepted something heinous about their respective Queequeg. Scully's dog was caught eating his dead previous owner. Ishmael's killed whales b) both were the best friend of their Queequeg and c) both died and were dragged down into the murky deep water by a creature. It would be a crocodile that kills the little dog, returning to the boggy land; Ishmael's friend dies in a coffin and goes down with the their ship "Pequod".