To stay with the 'consumer economy' tone of the film, from beginning to end there are approximately 73 companies who have product placements shown; from logos to actual items ranging in entertainment, electronics, fashion, food, hygiene, and cars. No money was received from all the product placements in the film.
Briefly during the airplane scene, Alexandra Cabot (Missi Pyle) breaks the fourth wall. Her brother, Alexander Cabot (Paulo Costanzo) wonders why she's even on the plane. She replies "Because I was in the comic book" and when he mis-hears her she corrects herself and says "Nothing."
Rachael Leigh Cook, Rosario Dawson, and Tara Reid had to go to a "Band Camp" for two weeks to learn how to play the instruments their characters used in order look correct on screen. However, they did not become proficient to the level that they could play effectively on the soundtrack. The actual music was supplied by studio musicians.
Early on, when Wyatt and Lex (the pilots of the private plane carrying boy band Du Jour), are about to escape via parachute, Wyatt enters the cockpit and says: "take the Chevy to the levee." This is a lyric from Don McLean's song, "American Pie", a song which - amongst many other rock & roll events - expresses sadness about the fatal plane crash which took the lives of Buddy Holly, Richie Valens, and J.P. Richardson (professionally known as The Big Bopper.
The "Bubbles" in the Mega Records recording studio change from white to yellow during the course of the film. Apparently the techs could not keep the material they were made out of to stay white, so they just went with it.
During the TRL scene, the cardboard cut-outs in the "audience" feature Johnny Depp (2), Gwen Stefani (2), Christina Aguilera (2), Britney Spears, and Matt Damon. Melody defends herself with Britney and Christina, but Carson Daly hits the cut-outs with a baseball bat. Melody eventually clubs Carson with the Matt Damon cut-out and knocks him off the bleachers.
Alan Cumming's character tells the girls how lucky they are to be able to go back to their 10 year high school reunion as huge successes. Three years earlier in the Romy and Michele's High School Reunion (1997) his character was the greatest success at the 10 year reunion. Likely this line was an intentional reference.
Tara Reid starred as the band's drummer, Melody Valentine. Not knowing how to play drums before they filmed, she needed to learn the basics so she could appear to know what she was doing behind the kit. The producers hired Drew Thomas, who was in such bands as Bold, Into Another, and Youth of Today.
Aaliyah was considered for the role of Valerie Brown. The film features a scene of a plane crash. Eerily enough she would then die in a plane crash on August 2001 four months after this film's theatrical release.