Wordpress Plug-ins
wp-microid - easily add MicroIDs to your site to enable ownership verification with services like ClaimID.
wp-openid - Enable OpenID-based authentication for commenting, account registration, and user login.
wp-yadis - provides the ability to use your own URL as an OpenID, but delegate the actual authentication to a third party, such as MyOpenID or LiveJournal.
Most projects are dual-licensed under the GPLv2 and Modified BSD.
