Geeklog

Geeklog is an open source blog application. Geeklog was initially released in 2000.

Geeklog is a CMS and blog engine with support for comments, trackbacks, multiple syndication formats, spam protection, and all the other vital features of such a system. The core Geeklog distribution can easily be extended by the many community developed plugins and other add-ons to radically alter its functionality. Available plugins include forums, image galleries, and many more.

Blog/CMS Features:

Create, Schedule, Post and Edit articles in multiple topics
Save story drafts until they are ready for publishing.
Control over formatting used in articles (HTML whitelists)
Control over acceptable content (filtering of offensive language)
Embed images or other content in articles
Multiple Authors can post
Submissions from users
Support for comments, trackbacks and pingbacks
Export and import in all common syndication formats (RSS/RDF/Atom etc)
Spam detection and rejection
Robust calendar feature with support for personalized calendars.
Support for OAuth, OpenID and other remote authentication methods.
Extendible via numerous Open Source plugins.

Administration Features:

User accounts and access controls.
Robust *nix-like security model for all objects which can be extended for use in plugins
Access can be defined for each article, topic etc
All passwords are stored encrypted.
All admin access is logged.
All errors are logged.
Complete error logging on all forms and SQL calls.

Developer Features:

Plugin support with API for developers.
A fully configurable block system, with php-in-block support.
Well organized codebase, use of PHP's Object-Oriented features.
Thin database abstraction layer allowing Geeklog to be ported to DBMS's other than the defaults (MySQL and MSSQL supported directly).