This game was originally called Crash Clash Racing, and it was going to be developed by Traveller's Tales Oxford Studio, the team that made Crash Twinsanity. Evil Crash was intended to be a playable character in their version.
A Nintendo DS version was originally in the works by Sensory Sweep. No screenshots or information were officially revealed before its silent cancellation. You can find out more about it here.
There is a hidden message in the Midway located near the turtle carousel. Jump on to the nearby kiosks as if you're heading towards Tomb Town, and if you look closely to the other side of the fence to your left, you'll see, in very small letters, the words "DR + NF". This was originally found by the user CrashHappy from the game's now defunct official forum. I looked for a match of these initials in the credits and found Dan Roarty's name (who was a 3D artist for the game), and after looking up his email address on the Internet, CrashHappy and I decided I should ask him about it. Dan confirmed our guess that this was an easter egg dedicated to his significant other. Apparently this had been the first time someone found it besides the people Dan told about it.
The user JumpButton was the first person to e-mail Darren Esau, who left his email address in the credits commentary (present only in the NTSC-U version). Darren stated in his reply that "[JumpButton] disproved [his] theory that the only people who read videogame credits are the developers themselves."
This game was chosen as the Best 2006 Video Game in the Nickelodeon magazine, and Crash was chosen as the Best Character, winning a total of 2 Golden Thumb Awards.
It was the first game in the series to be rated higher than E in NTSC-U regions (E+10) and higher than +3 in PAL regions (+6 and +7, depending on the country).
Pasadena seems to be based on Penelope Pitstop, an animated Hanna-Barbera character most famous for her roles in Perils of Penelope Pitstop and Wacky Races.
The music in some of the shooting mini-games is a minimalist version of the main Crash Twinsanity theme. This theme is also briefly heard in the final story cutscene, and it's remixed for the credits.
The Tragic Kingdom (a PSP-exclusive battle arena) reuses the music from Crash Twinsanity's Rooftop Rampage.
References
The Classic Crash skin and the first power gem cutscene are both tributes to Indiana Jones. The music in Pyramid Pass's last lap (when in 1st or 2nd place) is heavily based on Indy's theme.
The Space Crash skin is identical to the outfits worn by the crew in Star Trek, and Crash's eyebrows become similar to Mr. Spock's from the same franchise.
There are a lot of references to The Simpsons: Hit & Run, another game developed by Radical Entertainment. The people walking around the park say many lines from that game, and one of the game's text hints is: "Have you played Hit & Run? Man, that was a great game." The coin sound effects and the explosion animations come directly from that game, as Crash Tag Team Racing runs on an updated version of its engine.
Most characters have one line saying "I am [character's name], hear me roar!". This is a reference to Helen Reddy's song I am Woman (Hear me Roar).
Crunch in this game is basically a parody of Mr. T, an actor best known for his role a BA Barracus in the television show A-Team (the character's fear of flight is also referenced sometimes). He even has an unlockable skin named "Mr. Crunch", which makes him look like a bandicoot version of the actor. The reason he spews out random advice all the time is because Mr. T used to have PSA announcements on TV. Additionally, his car, the Overcompensator, features milk bottles on the back, a reference to Mr. T telling people to drink their milk. The line "Don't be a fool, stay in milk!" refers to a meme that jumbled up some of Mr. T's PSAs (the original line was, of course, telling kids to stay in school).
Chick and Stew are parodies of Howard Cosell and George Foreman, respectively. They are sports commentators with the same kind of voices and speech patterns.
The start line in Fossil Fuel Injection looks just like the entrance gate from Jurassic Park.
The music from Tire & Ice is a mix of several classic songs. It pulls bits from Bach's Double Concerto in the beginning and later throws in a few Russian themes, such as Karinka and, during the last lap in first or second place, Korobeiniki (better known as Tetris's Type A theme). The Hungarian Dance No. 5 is also included.
The music in Pirates of the Carburetor and Tiki Turbo is heavily based on the soundtrack from the movie Pirates of the Caribbean. The former's name is also a pun on it.
When racing in Evilocity, if the player is in third to fifth place during the last lap, the music switches to a recreation of the classic theme Night on The Bald Mountain.
Nina sometimes sings Bad Boys by Inner Circle, replacing the word "boys" with "girls".
Upon winning a race, Cortex will sometimes sing Who Let the Dogs Out? by Baha Men, relpacing the word "dogs" with "canines".
Cortex sometimes sings Rawhide when he starts the car after stopping.
Similarly, he will sometimes say "Burn, baby, burn! Like a Disco Inferno!", which may be a reference to the album Disco Inferno.
Other times he'll reference Back to the Future by saying "1.8 gigawatts of power!". In the movie, the protagonist needs 1.21 gigawatts of power to travel through time, but the way Cortex pronounces it ("jigawatts") is similar to how the characters do in the movie.
At one point Willie says "And I would have succeeded too, if it wasn't for you meddling bandicoots!". This was commonly said word for word by the villains in the old Scooby Doo shows, only with "kids" instead of "bandicoots".
Sometimes Crunch says "I burninated that chump!", which is a reference to a Homestar Runner character named Trogdor The Burninator. Another of his lines is "Ha ha, your car a splode!", again referencing a famous quote from Homestar Runner: "Your head a splode!"
When Coco's car explodes, she'll sometimes say "Awww, derryberries!". Derryberry is the surname of her own voice actress, Debi Derryberry.
The sign that says "Wet Dog" resembles the logo from Naughty Dog, the original Crash Bandicoot developers.
One of Coco's lines is "Top of the World, 'ma!", which is taken from the movie White Heat.
N. Gin sometimes says "I need more cowbell!", a reference to Saturday Night Live.
One of Pasadena's lines is "Striking me down will only make me stronger". A similar line is uttered by Obi-Wan in Star Wars Episode IV: A New Hope.
When hit by Crash, certain Park Drones may say: "What is your major malfunction?!", referencing the movie Full Metal Jacket.
N. Gin's line "There can be only one!" is a quote from the movie Highlander.
Two of N. Gin's lines are references to the Wonder Twins: "Form of... a killing machine!", and "Cybernetic merge powers... ACTIVATE!". Cortex says something similar: "Powers of Cortex... ACTIVATE!".
Talking to Cortex sometimes prompts him to explain that revenge is a dish best served with fava beans, a famous quote by Hannibal Lecter in the movie Silence of the Lambs.
N. Gin occasionally says "Sing the doom song!", referencing Gir from the Invader Zim show.
The park drone who sells the third crystal in Tomb Town impersonates Charlton Heston, a character from the movie Planet of the Apes.
Upon getting hit, one of the park drones in Astro Land quotes W. C. Fields's famous catchphrase: "My little chickadee!" This line is widely associated with the movie of the same name.
When driving off a ramp, Pasadena might say "'scuse me while I touch the sky", referencing Jimi Hendrix's song Purple Haze ("'scuse me while I kiss the sky").
There is a battle arena called "Fight Like an Egyptian", referencing the song Walk Like an Egyptian by The Bangles.
The battle arena called "The Tragic Kingdom" is a reference to a Walt Disney World theme park called The Magic Kingdom.
Many fairy tale stories are parodied in the game: Jack and the Beanstalk, Rapunzel, Cinderella, The Three Little Pigs, The Frog Prince, etc.
One of Nina's lines, "Super size me!" is a reference to the documentary of the same name.
Von Clutch often says "This reminds me of the Hindenburg!", a reference to the infamous German zeppelin that burned down in 1937.
Cortex's line: "Can you sense the antici... pation?" is a reference to the movie named The Rocky Horror Picture Show, where Dr. Frank N. Furter pauses during the word 'anticipation' in the exact same manner.
The park drone who sells Crash the skeleton outfit in Astro Land claims to be from "Drone Eye for the Bandicoot Guy", a parody of the television show Queer Eye for the Straight Guy.
The one who sells Crash the mad scientist outfit in Tomb Town talks like Boris Karloff, an iconic horror movie actor.
Von Clutch's line during races, "Wir fahr'n fahr'n fahr'n auf der Autobahn!" is from the song Autobahn by Kraftwerk, a German band. He also sometimes says "Musique non-stop, dummkopf!", which is a reference to another song from the same band, Musique Non-Stop.
The La Brea Tar Pits in Los Angeles are referenced by the race track Labrea Car Pits.