Smeagol is a customizable read-only Gollum wiki server. Smeagol makes it possible to maintain a standalone website, but update it through the Gollum wiki interface, e.g. via GitHub.

A simple library to wrap around some common wiki operations Currently only PMWiki is supported, but more will be added as and when.

WikiMD is an easy-to-use knowledge database, which has minimal system dependencies

redmine wiki exporter

Unlike a complete wiki engine, yaw is a wiki library to be embeded in your rails application.

A Ruby gem that serves a wiki from Markdown files in a local directory.

Liquid filter that converts wikilinks to markdown links

Protobuf client and server for the Wikipaddle API

Welcome use Wikiable!

With Caramelize you can migrate any wiki to git-based Gollum wiki repositories.

Junebug is a minimalist ruby wiki running on Camping.

GitHub wiki search for Ruboty

A Lita handler that returns a requested Wikipedia article.

Support for pulling/pushing wiki content from source repository to elexis.wiki

mount your fossil scm wiki on your filesystem

Watches a markdown git wiki for changes, automatically commits and pushes.

WikiWah is a text-to-HTML converter, along the lines of Markdown. This isn't the markup language you're looking for. It offers no improvements on Markdown, Textile, etc. I'm packaging it as a gem only because I still have some legacy content in this format.

A simple wiki for Utopia.

A Poundie plugin to post wikipedia pages to Campfire

Exports Trac wiki pages as local HTML files