Wiki.js - An open source, modern and powerful wiki app built on Node.js, Git, and Markdown.
DokuWiki - DokuWiki is a simple to use and highly versatile Open Source wiki software that doesn't require a database.
Oddmuse - Oddmuse is a wiki engine.
TiddlyWiki - a non-linear personal web notebook
MoinMoin - MoinMoin is an advanced, easy to use and extensible WikiEngine with a large community of users.
Scribbleton - The little personal wiki.