Trivia: In the scene where Harry and Malfoy are flying on their brooms, there's a shot where Colin takes a picture. Listen to the music right after that. The music is the same music used in Star Wars: Episode II - Attack of the Clones during the chase scene on Coruscant (John Williams did the music for this film and all the Star Wars films).
Trivia: The first scenes in the movie are some of the last scenes filmed. Viewers kind of tell by the way the actors' voices and looks changed. For example, Matthew Lewis (who played Neville Longbottom) said that he had to stuff cotton balls in his cheeks in the "Mandrakes in the Greenhouse" scene, since he had lost so much weight since the beginning of filming.
Trivia: When Harry, Ron and Fang begin to walk through the Dark Forest there is a close-up of Fang walking towards the camera. At the start of the next shot, at the bottom right of the screen the Ford Anglia is visible. Although the scene of them seeing the car before it rescues them is deleted, this one shot remains of the car 'watching' them. (01:43:40)
Trivia: There is an extra scene after the credits. You see the after effect of Lockhart's backfire of the 'Obliviate' spell.
Trivia: A trait of J.K. Rowling is to make up names that are pertinent or descriptive of their object/person (eg. Diagon Alley, Voldemort, etc). This is the same for Knockturn Alley: It is a place you wouldn't want to visit 'nocturnally'.
Trivia: In Philosopher's Stone (2001), Hagrid taps the bricks behind the Leaky Cauldron and as the bricks start to rearrange themselves creating the doorway, pause the film for the quick glance at the old green sign that reads, "Flourish & Blotts" which hangs over the corner bookstore. This is the bookstore in Chamber of Secrets that Harry and Hagrid pass on their way out of Knockturn Alley, but the old green sign obviously reads something else as it is not the setting for Flourish & Blotts in this film.
Trivia: In Asian releases of the film, the Chinese subtitles for 'Draco Malfoy' has a double meaning. It is pronounced as 'zhuai ge', which also means 'arrogant guy'.
Trivia: Christian Coulson landed the role as Tom Riddle, even though he was 23 at the time of filming, and exceeded the 15-17 age group set for auditions. Ironically, in 2007 when Coulson expressed an interest in returning for Half-Blood Prince, director David Yates declined, feeling that Coulson was "too old" to play the role again.