Avatar from URL
This plugin has been moved to my code archive.
This plugin looks at the comment author’s URL and tries to find a suitable image. This is primarily done by looking for an hCard, but it will also use other images if no hCard I found.
Put this code inside the comment loop:
<?php avatar_from_url(); ?>
Outside the comment loop you can also pass a specific URL to the function. A second argument of false will cause the URL to the image to be returned instead of writing the image tag into the page.