The artificial heart shown in the movie is actually a real artificial heart, the AbioCor from Abiomed. However the real artificial heart is totally internal and does not include a battery box as shown in the movie. The latest AbioCors can run on battery without recharging (done via external RF chargers) for over 4 hours.
Just before Chelios rips open the sidewalk electrical box, you can see the 5-star "Obey" logo popularized by Shepard Fairey, the artist who drew the emblematic "Hope" poster of Obama. Fairey got his artistic start with graffiti and by putting up stickers like Obey all over urban landscapes.
There is a scene where Chev Chelios attempts to shoot a man cowering on the floor, and when he pulls the trigger and finds the gun empty, utters the line "you lucky bastard!". The same scenario also appears in Snatch. (2000), which also stars Jason Statham, only the antagonist in that scene is Vinnie Jones.
In the scene where Chelios runs into a mob of porn stars, the "extras" in the movie are real porn stars. One of the stars most recognizable is Jenna Haze, but Peter North and Ron Jeremy make an appearance as well.
The Concerned Man who is seen very briefly asking Chelios if he's okay is played by UFC mixed martial artist Keith Jardine. Jardine is wearing a shirt that says "MEAN 1". This is appropriate as Jardine's in-ring nickname is "The Dean Of Mean".
When Chev breaks the battery pack to his artificial heart towards the beginning of the movie, the circuit board shown is from a USB hub.
A rather large organ can be seen on the pelvic x-ray near the beginning of the movie.
Cameo: [Maynard James Keenan] The man with the control to the electric shock collar is the lead singer of prog-metal band Tool.
Cameo: [Danny Lohner] The man accompanying the owner of the shock collar that Chev Chelios steals is Danny Lohner, of Nine Inch Nails and various other industrial projects.
There were two cameras used to make this film: The Canon XH-A1 and these micro cameras, the Canon HF-10.