In the last post of this series (you can find the first two posts here and here), I wanted to talk about Stephen King books that aren't necessarily related to The Dark Tower, but are connected to other Stephen King books. As always, this isn't a comprehensive list.
Note: This post may include spoilers.
Let's start with IT, because it's connected to several novels.
IT and Dreamcatcher: In Dreamcatcher, there's a plaque that mentions The Losers' Club and main characters, Beverly, Bill, Mike, Richie, Stan, Eddie, and Ben, all from IT. This plaque also mentions Pennywise, the clown from IT.
IT and 11/22/63: Beverly and Richie from IT make an appearance in 11/22/63.
IT and Christine: In IT, the ghost car Belch Huggins drives when he picks up Henry Bowers is Christine.
IT and Misery: Eddie Kaspbrak's mom and Paul Sheldon's family were neighbors.
Misery is also connected to another book, The Shining. In Misery, Annie Wilkes mentions a man burning down the Overlook Hotel; she's referring to Jack Torrance.
IT and The Dead Zone: In a dinner scene in IT, The Losers talk about Frank Dodd, a character in The Dead Zone.
Speaking of The Dead Zone, it's connected to Cujo, which is also connected to other novels. Cujo and The Dead Zone are connected by Frank Dodd, who is mentioned in Cujo. George Bannerman is also a character in both novels.
Cujo is also connected to Pet Sematary; Jud Crandal, a character in Pet Sematary, mentions Cujo. Pet Sematary is connected to Insomnia, as well; Atropos, a character in Insomnia, has a shoe that belonged to Gage Creed, a character in Pet Sematary.
Cujo has two additional connections, one to a novel, and one to a novella. Cujo is connected to Needful Things and The Body (found in Different Seasons) by the character Evelyn Chambers, who is present in all three works. In addition, Needful Things and The Body share a second character, Ace Merrill.
Needful Things is connected to The Dark Half; Alan Pangborn is the sheriff in both novels.
Last, there are some novels that have smaller connections, to only one or two other novels at the most. The first is Dolores Claiborne and Gerald's Game. The two books were going to be part of a larger work, titled In the Path of the Eclipse. The eclipse in Dolores Claiborne is mentioned in Gerald's Game, and the main characters in each story (Dolores Claiborne and Jessie) have a psychic connection, allowing them to share visions.
The second is Firestarter, The Mist, and The Tommyknockers, which are connected by an organization called The Shop, that plays a large role in each story.
Know of any other connections? Tell us what they are in the comments!