Crash Interview (Official Crash Bandicoot Magazine)(contributed by Tropy29)
This interview appeared in the first (and only) issue of the Official Crash Bandicoot Magazine, which was primarily created to promote Crash Twinsanity before its release. It contains a rare sighting of Crash's autograph. As you can see, Crash is one heck of an actor.
Cortex Interview (Toxic magazine)(contributed by Danju Parker and Crashinator7)
An interview with the bearded scientist himself, as featured in an issue of Toxic. It was used to promote Crash Tag Team Racing.
Disney Adventures CTR Comic(contributed by Ben-F and All Star Blitz)
This is an old comic featured in the Winter 2000 issue of Disney Adventures, which also contained comics of other video-games such as Rayman 2, Toy Story 2, Donkey Kong 64 and Ape Escape. The comic, drawn by animator/cartoonist Neal Sternecky, features a short story about a CTR race, including several references to the gameplay and even cheats randomly spread across the panels.
This comic is also notable for giving Crash full dialogue and mentioning the scrapped plot element of the X Device, a machine created by Nitros Oxide capable of speeding up anything.
Game Informer #66 (October 1998)(contributed by Keiji Dragon)
Four pages detailing Game Informer's experience with Naughty Dog and the WARPED demo they got to play before the game's release. It also features several interesting facts about the original trilogy's development, not the least of which was the fact that Naughty Dog gave Crash 1 the nickname "Sonic's Ass Game" during development, in reference to the then unusual behind-the-back camera angle.
WARPED 4-Koma(contributed by Pur)
The official Japanese guides would sometimes feature humorous stories in 4-Koma format (short comics with four panels). The WARPED guide features one drawn by Ari Kawashima, who also created the Dansu! De Jump! Na Daibouken manga.
Note that stories are displayed in columns, so be sure to read vertically from top to bottom.
CTR 4-Koma(contributed by FierceTheBandit)
Another 4-Koma collection, this time taken from CTR's official Japanese guide.
Crash Bash 4-Koma(contributed by Fernys)
And one more for the trip, this time taken from Crash Bash's official Japanese guide.
The Wrath of Cortex Interviews and Backstory(contributed by B-Mask)
The official guide for The Wrath of Cortex features some interesting developer interviews and the story up to that point. It's worth noting that this backstory incorporates non-canonical elements from the original game's production bible, such as Cortex's circus past. It also explains that Tawna broke up with Crash to stay with Pinstripe, which is actually only part of the Japanese canon. Interestingly, there is some foreshadowing to Crash Twinsanity, though this was probably unintentional given that the story for that game wouldn't materialize until several years later.
School & Youth Programs(contributed by Danyel)
Back in 2007, Crash became the official mascot for the School & Youth Programs, a part of the Leukemia and Lymphoma Society. There were several promotions using Crash of the Titans and Mind Over Mutant artwork to raise awareness of these conditions, including downloadable wallpapers.