Trivia: Johnny Depp passes an old bald man with hippy glasses sitting down surrounded by women - this is author Hunter S. Thompson himself in a cameo.
Trivia: In the flashback where Johnny Depp takes LSD in the bathroom of a 60's bar, the hippy who starts to lick the LSD he dropped is Red Hot Chili Peppers bassist Flea.
Trivia: Photos of Hunter Thompson in the 70s confirm just how accurate Johnny Depp's costume is. This is because Hunter Thompson actually lent him some of his old clothes for the part.
Trivia: Hunter S. Thompson has a cameo in the film: At the beginning of Duke's flashback to The Matrix, his voiceover says, "There I am. Jesus." as he looks at a man with sunglasses none other than his real life alter ego.
Trivia: During the first flashback (from the car in the desert to the hotel where Duke gets the assignment for Las Vegas), the midget actor who played the bellhop bringing him the telephone also played a hotel bellhop in the 1980 film "Where the Buffalo Roam," which was also about Hunter S. Thompson and starred Bill Murray.
Trivia: When Duke is calling Dr. Gonzo at his law office from the desert, look in the background of the office. You'll see a black poster with a white star and red fist on it. This poster is from Hunter S. Thompson's run for the seat of sheriff of Pitkin County in Colorado, under the "Freak Power" ticket. During the election, Thompson shaved his head bald, and called his opponent, who sported a crew cut, "my long-haired opponent". Thompson lost by a mere 500 votes.
Trivia: Actor Johnny Depp first met Hunter S. Thompson in Aspen, Colorado just before New Year's Eve, 1995. Depp left that initial meeting wondering why Fear and Loathing had not been made into a film. The actor subsequently invited Thompson to do a one-night gig at the Depp's nightclub, The Viper Room on September 29, 1996 with the intention of asking the writer about doing a film version of his book. The opportunity never materialized but the two began corresponding via faxes. Early one day, Thompson called Depp on the phone and asked him if he would consider playing Raoul Duke if a film was ever made of Fear and Loathing. "Without hesitation, I said, 'You bet!'" Depp recalls. By the Spring of 1997, Depp had moved into the basement of Owl Farm, Thompson's home in Aspen in order to do proper research for the role. Depp was given complete access to every memento the writer saved from his 1971 trip to Las Vegas. The actor read through the writer's notebooks (which included an unpublished chapter entitled, "The Coconut Scene," which Gilliam placed in the film) only to realize that "the freakiest thing was that it was all real, that the reality was as insane as the book." He rummaged through Thompson's wardrobe at the time: Hawaiian shirts, a patchwork jacket, a safari hat, and a silver medallion given to him by Acosta (Dr. Gonzo). Thompson graciously allowed Depp to wear it all in the film. Thompson even let Depp borrow the red shark: the giant fire engine red convertible that the author took to Vegas, which was also used in the film.
Trivia: Johnny Depp's haircut was done by Hunter S. Thompson.
Trivia: For the drug scenes, Johnny Depp snorted powdered milk, which has the appearance of cocaine.