When Natalie is in the Red Star mainframe, she lifts up a computer board where she installs the antenna. The computer board is the motherboard of an Apple PowerMac G3. You can see the FireWire and USB ports and the wave-design back panel.
The Thin Man, played by Crispin Glover, originally had a speaking role, but Glover didn't like the lines, so he asked for them to be removed. The director and producer agreed to make it a non-speaking role to give the character a more mysterious feel.
The hillside house is modeled after a real California architectural landmark, the Chemosphere House created by architect John Lautner. The entire house was created on a soundstage and was actually much larger and rounder than the original.
The speaker sitting on Bosley's desk, through which the Angels hear Charlie's assignments, is almost the same as the one used in the TV series (Charlie's Angels). The speaker in the original series had a small "Bell" in the lower corner, the movie version did not.
The secret language the Angels use is Finnish, though very poorly pronounced. They said in Finnish: Alex: "Onko sinun ja Knoxin välillä menossa jotain?" Dylan: "Ei tietenkään." Natalie: "On vain niin, että suhteet asiakkaiden kanssa ovat tosi huonoja ideoita." Dylan: "Olen samaa mieltä." Translated roughly in English: Alex: "Is there something going on between you and Knox?" Dylan: "Of course not." Natalie: "It's just that relationships with customers are very bad ideas." Dylan: "I agree." Drew Barrymore's pronunciation was the best.
Drew Barrymore bought the screen rights to Charlie's Angels prior to the movie being filmed - a decision that earned her an estimated $40 million for the first film and a possible $80 million for the second.
Drew Barrymore was a huge "Harry Potter" fan, even going so far as to read bits of the books to the cast and crew during production. At the beginning of the film, during the clips of previous jobs, she can be seen wearing a Harry Potter disguise, complete with robes, black hair and round black glasses.
An in-joke in the opening scene has a character react to the in flight film "T.J. Hooker - The Movie" with "Oh no, not another movie based on an old TV show!". On July 6, 2009 it was announced that T.J. Hooker: The Movie, based on T.J. Hooker, was in development.
In the scene at the Japanese themed party, when Natalie first meets Pete, he greets her with "konichiwa", Japanese for "Hello", and she responds "Nihongo no shaberu no sugoi ne!" which means "You speak Japanese very well!"
The film's martial arts choreographer and trainer appears as a fellow passenger on the plane in first class at the start of the film. He can be seen speaking in Cantonese to two pretty women, teaching them to say "thank you".