Trivia: When Anakin is walking around the bar in Coruscant looking for the changeling, he passes Ahmed Best, the voice of Jar Jar Binks, and we also see Anthony Daniels, who plays C3-P0. Katie Lucas (George Lucas' daughter) is also visible.
Trivia: In one of the trivia books about the movie, there is a page where the different beverages sold at Dex's Diner are illustrated. One of the substances is labelled 'Alludium PU-36.' Alludium PU-36 is the 'explosive space modulator' that Marvin the Martian attempted to use to blow up the earth in the Warner Brothers Bugs Bunny cartoon.
Trivia: After the fight scene between Obi-Wan and Jango Fett at Kamino, as Jango runs up the walkway into his ship, the door closes from above and knocks Jango in the head as he enters. Deliberately done - a little nod to the Storm trooper in Star Wars. While there's no proof (yet) that all storm troopers are clones (films are the only canon, remember), this seems to suggest that a few years down the line at least some are, and have inherited their "father's" occasional clumsiness. Confirmed in the commentary.
Trivia: The vehicle that Anakin steals for the Coruscant chase scene has deer whistles on it, right behind Anakin and Obi-Wan's heads. For those that don't know what deer whistles are, they are small whistles that mount on the bumper of your car and make a high-pitched noise (too high for human ears but perfect for animals) to scare deer off the highways.
Trivia: The tower where Dooku meets Sidious at the end of the movie is obviously incomplete (unfinished parts can be seen). It also looks very much like the Emperor's Citadel, briefly seen in the cutscenes of the Tie Fighter computer game (then, completed).
Trivia: Jett Lucas (the son of George Lucas) appears as a young jedi padawan, and Katie Lucas (George's daughter) appears as a twilek in the Coruscant bar.
Trivia: When Anakin tells Padme that he killed all the Tuskin Raiders, (the "I killed them, I killed them all..." speech) it is an almost word for word copy of Ralph Macchio's speech in 1983's "The Outsiders".
Trivia: When Obi-Wan Kenobi meets with Dexter Jettster, and they hug, Obi-Wan was computer generated from the neck down.
Trivia: In the original script, Jango Fett appeared in the Geonosian meeting room with Count Dooku and the other leading Separatists (that Obi-Wan is looking down into), but was removed from the final cut because the filmmakers didn't want to immediately give away that Dooku was the villain.
Trivia: Samuel L. Jackson is reported to have "B.M.F." engraved into the handle of his lightsaber. B.M.F. is short for "Bad Mother F***er" and was stitched on the wallet of Jackson's character, Jules, in "Pulp Fiction."
Trivia: C-3PO was originally to have made his first appearance still in skeletal form. In post-production, Star Wars creator George Lucas decided to have C-3PO be complete throughout the film.
Trivia: In the floating pear scene, we see what type of cutlery they used a long time ago in a galaxy far, far away. It turns out to have been designed by the great Danish designer Arne Jacobsen, who is famous for his egg-shaped chair. But there may be a reason that Lucas used this cutlery - aside from looking futuristic, it is also the cutlery they use in 2001: A Space Odyssey.
Trivia: When Obi-Wan is in the Jedi library, he is looking at one of the busts. It is a bust of Count Dooku - it's mentioned in the secondary literature that he is one of the Lost Twenty, which are represented by the 20 busts in the Archives. These 20 are the only ones who left the Jedi Order.
Trivia: When Obi-Wan is getting the tour of the cloning facility he looks up to the ceiling and the camera shot switches to show some equipment moving. It seems like a senseless shot that doesn't fit with the rest of the scene. If you look closely you will notice that the piece of equipment is actually the saucer section of a Star Trek starship, possibly Voyager or the Enterprise -E.
Trivia: One of the inside jokes by the ILM crew concerns the cow-like creatures that Anakin rides on Naboo. One can be found in the asteroid field surrounding Geonosis, and one can be seen during the Battle of Geonosis, in the background, running, and on fire.