XWiki is a WikiWiki clone written in Java that supports many popular features of other Wikis like the Wiki syntax, version control, attachments, security, and searching, but also many advanced features like templates, database and dynamic development using scripting languages (Velocity, Groovy, Ruby, Python, PHP, and more), an extension system and skinability, J2EE scalability, an XML/RPC remote API, statistics, RSS feeds, PDF exporting, WYSIWYG editing, an Office viewer and importer, and a lot more.
FUDforum is a templatable forum with i18n support based on PHP and either MySQL, Oracle, PostgreSQL, or SQLite. It features a user/group management system, a multi-lingual spell checker, both flat and thread message views, a private messaging system with multi-user forwarding capabilities, poll file attachments, and much more. It is an extremely fast and scalable forum that can fulfil the needs of both small and large forum operators.
Mueller-dict is an electronic version of popular the English-Russian dictionary by professor V. K. Mueller in DICT format. It currently contains more than 50,000 articles and represents a full copy of the 7th edition of the mentioned dictionary, with some additions and corrections sourced from the more recent typographical editions. It includes phonetic transcription in the IPA (International Phonetic Association) system optimized for proper rendering on text terminals with standard Cyrillic fonts.
Gollem is a Web-based file manager that provides the ability to fully manage a hierarchical file system stored in a variety of backends such as a SQL database, as part of a real filesystem, or on FTP, Samba or SSH servers. It supports uploading and downloading of files, basic file operations, permissions support, and MIME recognition and viewing of files through the Horde MIME library. It is fully internationalized and translatable.
Byteflow is a blog engine written on Django. It features Markdown and typogrify for posts and comments, threaded comments, automated registration for a user after comment posting (no anonymous users), registration approval/email changing/profile editing, tags (and filtering posts by tag), the ability to have translated names for tags, archives by day, month, and year, Atom and RSS Feeds for posts, comments, comments for a specified post, posts within a specified tag, and OpenID support. It supports multiple OpenID URLs attached to a single user, a Wordpress importer, Gravatar, an optional WYSIWYG editor in admin parts (for posts, not for comments), and LiveJournal crossposting.