MindTouch Deki Wiki – Open Source Wiki and Application Platform
http://wiki.mindtouch.com/Deki_wiki

MindTouch Deki Wiki is a free open source wiki and application platform for communities and enterprises. Deki Wiki is an easy to use and sophisticated wiki for authoring, aggregating, organizing, and sharing content. Deki Wiki is also a platform for creating collaborative applications, or adding wiki capabilities to existing applications. This has been added to the tool section of Research Resources Subject Tracer™ Information Blog. This has been added to World Wide Web Reference Subject Tracer™ Information Blog.