Erunafailaro

This plugin is intended to make the comment-moderation for the blog-owner a little bit easier. It does not detect comment-spam on its own. To successfully prevent spam, it should be used as an addition to the spam-protection provided by Akismet and Spam Karma.
This plugin adds a small button to every comment. This button will only be visibly to a logged-in blog-admin (that is a registered user with a user-level of 10).
When you press this button, the URI of the commenter will be replaced by the URI you can specify at the plugin?s option-page.
<h3>Plugin Homepage</h3>
The complete documentation is located at my website: http://www.weinschenker.name/comment-url-control/

Comment URL Control

This plugin will allow you to remove an unwanted author-URI entered by a commenter with one single click of your mouse.

mihai

This plugin will modify the links on pingbacks (and trackbacks) to remove the 
“external nofollow” for links to your own blog.
More info:
<ul>
<li><a href="http://patchlog.com/follow-self-pings/" rel="nofollow ugc">Follow Self Pings plugin</a>.</li>
<li>Check out the other <a href="http://patchlog.com/wordpress/" rel="nofollow ugc">WordPress plugins</a> by the same author.</li>
</ul>

Comment URL Control vs Follow Self Pings