Personnal or familly wiki with low ressource requirement.
Personal lightweight wiki based on DidiWiki. Upgraded to accept text and highlight color, image resize and video (youtube, dailymotion...) embedded. Written in C, doesn't require a lot of RAM. Works fine on Raspbian (Raspberry Pi).
Example of Ciwiki running on Raspberry Pi B+ (700MHz, 512MB):
http://inphilly.dyn.dhs.org
The collection of extensions for MediaWiki software.
...The Multi-Category Search extension allows users to find wiki pages that are included in several specified categories at once.
MS SQL Database Authentication extension authenticates users and gets users data from external Microsoft SQL Server database.
Ticket Authentication extension provides customizable ticket-based authentication for SSO solutions.
The News Channel extension creates customizable automatically updated RSS/Atom news channel for a wiki site. Wikimarkup is automatically converted into HTML.
See full descriptions at http://www.mediawiki.org/wiki/User:CodeMonk/MediaWiki_Extensions
Hatta is a wiki engine that uses a Mercurial repository for storing the pages. You can run it as a web application on your server, or locally on your computer. You can also do both, and synchronize the repositories once in a while.
A Wikipedia bot (a computer program designed to make automated edits to Wikipedia). It is written in Standard C - C99 - using the standard libraries and libcurl.
This project has not met its long-term goals, and has been abandoned.