MediaWiki - MediaWiki is a free software wiki package written in PHP, originally for use on Wikipedia.
Ardoq - Software Architecture Diagram Tool. Single platform for textual and visual documentation; Automatically generated diagrams based on data; Model driven .
TiddlyWiki - a non-linear personal web notebook
BiZZdesign - Enterprise Architecture software that helps organizations dramatically increase the success rate of complex enterprise transformation, strategic investment allocation, and risk management.
Confluence - Confluence is content collaboration software that changes how modern teams work
iServer365 by OrbusSoftware - The Next Generation SaaS Platform for Architecting Your Digital Future.