YubiKey enabled CMS plugins
Wordpress, Joomla, Drupal are examples of popular Web CMS systems with YubiKey support and there are several other YubiKey strong authentication enabled Open Source Web Content Management Systems for organizing and publishing content in an easy and collaborative way.
Some of the CMS plugins are written by Yubico but most are written by other Open Source authors. You can find more details for the YubiKey CMS plugins and Web collaboration Open Source systems supporting YubiKey on Yubico Wiki following the link below.