QuasiWiki
QuasiWiki implements some of the basic principles of wiki in OpenOffice.org Writer. It doesn't turn OpenOffice.org into a fully fledged wiki tool (hence the "quasi" prefix), but rather adds some wiki-like capabilities.
QuasiWiki is very much the work in progress. Send your ideas, improvements, suggestions, and comments to dmpop at openoffice dot org.
txt2tags extension
txt2tags is a so-called document generator that can convert a text file into several formats, such as HTML, XHTML, SGML, LaTeX, MoinMoin wiki and others. More importantly, txt2tags supports some basic markup and different configuration options that allow you to format your text file and do some other clever stuff. txt2tags' markup resembles a wiki's, and it is extremely easy to use. Although the list of markup tags supported by txt2tags is not as extensive as in an average wiki, it still includes the most used ones, such as titles, lists, links, images, and tables, as well as the so-called beautifiers (bold, italic, underline, etc.).
The txt2tags extension allows users to apply txt2tags markup to the currently opened document. It is not required for running QuasiWiki, but it makes a nice addition to it.