Twine
Another installment in bizarrely specific CMSs that I love – Twine is a CMS/tool for creating “interactive fiction.” Think text adventures like Zork, or gamebooks like the Choose Your Own Adventure series.
You don’t need to write any code to create a simple story with Twine, but you can extend your stories with variables, conditional logic, images, CSS, and JavaScript when you’re ready.
It’s basically a very specialized static site generator. There’s a repository of stories created from it: The Interactive Fiction Database.
(Incidentally, I got new bookshelves last month, and now I’m absolutely going to collect all 185 CYOA titles someday.)