DokuWiki is a standards-compliant, simple-to-use Wiki mainly aimed at creating documentation of any kind. It is targeted at developer teams, workgroups, and small companies. It has a simple but powerful syntax which makes sure the datafiles remain readable outside the Wiki, and eases the creation of structured texts. All data is stored in plain text files, so no database is needed
SimplyBibTeX is an application to share and hold BibTeX bibliographies. One can add, edit and remove entries from bibliographies online or upload complete collections. The system uses a very simple but effective template mechanism. Users and coworkers can subscribe to RSS 2.0 or Atom feeds in order to get notified about changes.
Pie is a lightweight content management system for Web-sharing documents, files, and arbitrary pieces of information. Making use of a Wiki's meta language and page-linking abilities, it lets authors create and maintain content via HTTP on a corporate basis. It features an emphasis on fast content delivery to its recipients rather than sophisticated add-ons, therefore conveying compiled output instead of performing time consuming run-time processing.
Tartan is a text parsing engine targeted at wiki text. The syntax specification is defined in YAML in the form of regex-based rules. It supports layering and multiple output types. Rules for Markdown to HTML are included, with optional layered extensions for tables. It is implemented in Ruby, but looking to have implementations in other languages.
WikklyText is a Python-based wiki and modular library for creating custom wikitext rendering applications. Its wikitext engine is compatible with the TiddlyWiki markup language. It functions equally well as a wiki-on-a-stick or as a multiuser wiki behind Apache. It includes a Drupal plugin as well.
PottyMouth transforms completely unstructured and untrusted text to valid, nice-looking, completely safe XHTML. PottyMouth is designed to handle input text from non-technical, potentially careless, or malicious users. It produces HTML that is completely safe, programmatically and visually, to include on any Web page. You don't need to make your users read any instructions before they start typing. They don't even need to know that PottyMouth is being used.
The Java Wikipedia API (Bliki engine) is a parser library for converting Wikipedia/Mediawiki syntax to HTML. It supports wiki tags for bold, italic, headers, nowiki, source, table of contents, tables, lists, categories, footnotes (references), images, syntax highlighting of source code fragments, templates, and template parser functions.