DokuWiki - DokuWiki is a simple to use and highly versatile Open Source wiki software that doesn't require a database.
Abstract - A secure, version-controlled hub for your design files
TiddlyWiki - a non-linear personal web notebook
Zeplin - Collaboration app for UI designers & frontend developers
MediaWiki - MediaWiki is a free software wiki package written in PHP, originally for use on Wikipedia.
ActiveWords - Auto correct on steroids