When Dwayne Johnson ('The Rock') was attached to star, this film was known as The Rock Movie. When he left to work on The Mummy Returns (2001), it was listed for a short while as Untitled Sci-Fi Project, and when Jet Li came aboard, it became The One.
Some characters have the last names of movie directors: Woo, Scott, Yates, Siegel, Besson.
As T.K. prepares to leave to see Gabe in the hospital, the TV in the background is playing a scene from Final Destination (2000) which was written and directed by 'Wong, James', the director and co-writer of The One. Also, when Funsch is entering in new coordinates for Gabe, the computer flashes up "Destination Final"...
For the martial arts aficionados: Jet Li uses two distinct kung fu styles when portraying Gabe and Yulaw. The evil Yulaw uses Xingyi Quan, or "Mind-Form Fist" (loosely translated). As can be seen when he is training, it is a very linear, offensive style. Gabe on the other hand practices Bagua Zhang, or the "Eight Trigrams Palm". It is characterized by open palm fighting, with circular footwork. Both styles are two of the three main "internal" styles of Chinese kung fu - the third being Taiji Quan (Tai Chi).
As someone mentioned earlier, Yulaw uses xingyi quan. There is a scene in the movie where is he practicing his xingyi when he's shackled and jailed. This is a reference to the famous Xingyi master Kuo Yun Shen who did the same thing when he was jailed.
The character, Roedecker (played by Delroy Lindo), shares his unusual name with the Millennium Group technician in the second season of the television program _"Millennium" (1996)_. Roedecker was introduced in an episode written by James Wong and Glen Morgan (who wrote, produced and directed The One).
When the police are chasing Yulaw by car at the beginning of the movie, a poster for One Night at McCool's (2001) can be seen briefly.
The scenes involving Jet Li fighting himself were shot using Li and a stuntman with a build similar to his. The stuntman's face was painted green so that it could be digitally replaced with Li's face later.
The 'University Medical Center' where Gabe goes for the MRI is the North Hollywood Medical Center where the popular sitcom "Scrubs" (2001) is filmed.