michelem

This WordPress plugin remove the “nofollow” attribute from your wordpress blog’s comments (precisely from the author’s links) and/or from the comments text links and it inserts (if you want) an image band at the top of your pages with the phrase: “NOFOLLOW FRE” to encourage your users to submit comments. 
The last release includes new options to replace the nofollow only when the author posted X comments before and put back the nofollow when some blacklisted words are matched. The replacement of the nofollow is also based on the users type (registered and visitor users). Every option cna be customized by the options page “NOFF”.
NoFollow Free now is multilingual, it supports English, Spanish, Italian, German, Turkish, Swedish, French, Portuguese, Romanian, Russian, Danish, Arabic, Croatian, Norwegian, Indonesian, Dutch, Hungarian, Chinese, Japanese, Polish amd Finnish languages.
Now it comes with a nice sidebar Widget support to show the top ten charts for the top commenters.
<h3>Usage</h3>
When you activate the plugin it just works removing the “nofollow” attribute from your comments authors link, but if you would like have the image band at the top of your pages too, you MUST put the php function into your template file just below the attribute like this:
<pre><code><body>
<?php if (function_exists(noff())) noff(); ?>
...
</code></pre>
Remember to set the plugin option by clicking wp-admin -> options -> NOFF
<h3>Infos</h3>
You could find every informations here and much more at http://www.michelem.org/wordpress-plugin-nofollow-free/

NoFollow Free

NoFollow Free removes the "nofollow" tag from your Wordpress blog's comments with a lot of custom options and provides the option to in …

Khang Minh

This plugin gives you total control over external links on your website. This plugin also comes with a comprehensive domain filtering feature. BWP External Links is based on the popular Prime Links phpBB mod by Ken F. Innes IV (Prime Halo).
Demo
If you want to see this plugin in action, you can either visit <a href="http://betterwp.net" rel="nofollow ugc">Better WordPress</a> or <a href="http://wordpress.grc.nasa.gov" rel="nofollow ugc">a user’s website</a> (NASA Glenn Research Center’s Website).
Tutorials
Check out this <a href="http://betterwp.net/wordpress-tips/redirect-external-links/" rel="nofollow ugc">redirect external links tutorial</a> for some tips on how to set up a redirection/disclaimer page using BWP External Links.
Some Features
<ul>
<li>Process links for post contents, comment text, text widgets, or the whole page</li>
<li>Domain filtering:
<ul>
<li>You can specify which sub-domains of your website to consider local (all subdomains, no subdomain, or some)</li>
<li>You can specify which external domains to consider local</li>
<li>You can forbid certain external domains (e.g. pron.com or warez.com) and replace URLs linking to them with a URL of choice (useful for filtering links in visitors’ comments)</li>
<li>Wildcard support, e.g. <code>*.example.com</code>, <code>*.subdomain.example.com</code></li>
</ul>
</li>
<li>You can add <code>rel="external"</code>, <code>rel="nofollow"</code> or any custom relation tag you could think of to external links</li>
<li>You can specify CSS classes for both local and external links, as well as external image links</li>
<li>You can use provided CSS rules (an external icon is added to each external link) or define your own</li>
<li>Choose whether or not to open a completely new window for each external link</li>
<li>Choose between three ‘new window’ modes: <code>onclick</code> attribute, <code>target</code> attribute or jQuery</li>
<li>Add a prefix to external links. Example use would be a redirection page that warns your visitors about the danger of visiting external sites, e.g. <code>http://yourdomain.com/out?</code></li>
<li>WordPress Multi-site compatible</li>
<li>And more…</li>
</ul>
It is highly recommended that you give the <a href="http://betterwp.net/wordpress-plugins/bwp-external-links/#usage" rel="nofollow ugc">Official Documentation</a> a good read to make the most out of BWP External Links.
Please don’t forget to rate this plugin <a href="https://wordpress.org/support/view/plugin-reviews/bwp-external-links?filter=5" rel="ugc">5 shining stars</a> if you like it, thanks!
Get in touch
<ul>
<li>Support is provided via <a href="http://betterwp.net/community/" rel="nofollow ugc">BetterWP.net Community</a>.</li>
<li>You can also follow me on <a href="http://twitter.com/0dd0ne0ut" rel="nofollow ugc">Twitter</a>.</li>
<li>Check out <a href="http://feeds.feedburner.com/BetterWPnet" rel="nofollow ugc">latest WordPress Tips and Ideas</a> from BetterWP.net.</li>
</ul>
Languages
<ul>
<li>English – default</li>
<li>Danish – Danske (da_DK) – Thanks to <a href="http://runit.nu" rel="nofollow ugc">Randi</a>!</li>
<li>Malaysian (ms_MY) – Thanks to <a href="http://d4rkcry3r.com/" rel="nofollow ugc">d4rkcry3r</a>!</li>
<li>Dutch (nl_NL) – Thanks to Juliette!</li>
<li>Serbo-Croatian (sr_RS) – Thanks to <a href="http://www.webhostinghub.com" rel="nofollow ugc">Web Hosting Hub</a>!</li>
</ul>
Please <a href="http://betterwp.net/wordpress-tips/create-pot-file-using-poedit/" rel="nofollow ugc">help translate</a> this plugin!
Visit <a href="http://betterwp.net/wordpress-plugins/bwp-external-links/" rel="nofollow ugc">Plugin’s Official Page</a> for more information!

Better WordPress External Links

Gives you total control over external links on your website.

NoFollow Free vs Better WordPress External Links