Tiki can be an application wiki, or be used to build situational applications.
This is done mostly by combining Pretty Trackers, plugins such as PluginGroup and PluginTrackerItemField and Category Transitions with the wiki. Now, that you can have tests, you can build forms like a mini-workflow.
Related:
http://platform.xwiki.org/xwiki/bin/view/Main/SecondGenerationWiki
http://twiki.org/cgi-bin/view/Codev/TWikiApplication
Related