I recently learned about MicroID, a microformat for verifying ownership of content on web pages, from a post on Phil Windley’s blog. MicroID, which is a simple hash of an email address and a URL, can be used to claim ownership of a blog, a blog post, or a blog comment.

Phil developed a MicroID plugin for MovableType.

Likewise, I created a MicroID plugin for WordPress [zip].

This WordPress plugin does three things:

1. Inserts a MicroID meta tag in the head of your blog. This is calculated from the administrator email and the blog URL listed in your WordPress blog’s General Options.
2. Attaches a MicroID to each post. This is calculated from the email address of the author of that post (which may be different if your blog has multiple authors) and the permalink of that post.
3. Attaches a MicroID to each comment. This is calculated from the email address and URL submitted with each comment.

This a very new concept with little practical application so far, but the possibilities are interesting: “Blog comment systems can check the given email address against a MicroID from the entered home page link to help reduce link spamming and blatant spoofing.” (microid.org)