guido

Remove IP it’s a really-really-simple plugin to not log the IP address from the people that comment on your wordpress 
installation.
This plugin will be useful to people that cannot/or don’t want to use <a href="http://riseuplabs.org/privacy/apache/" title="libapache2-mod-removeip" rel="nofollow ugc">libapache2-mod-removeip</a> (because you don’t use 
apache or don’t want to wipe out the IP logging on all vhosts).

Remove IP

The plugin does exactly what its name suggests: it removes the IP address from new comments on your blog – not more and not less.

Simple and efficient

A simple plugin to not log IPs from comments.

sander85

This plugin allows to block spammers with the following options:
<ul>
<li>Block spammers by IPs (supports wildcards).</li>
<li>Block IPs that have posted comments marked as spam.</li>
<li>Block comments that contain bad words.</li>
</ul>
Additional options:
<ul>
<li>If comment contains bad words, add the spammers IP into the blacklist.</li>
<li>When deleting spam, add IPs of spam comments into the blacklist.</li>
<li>Similar entries in the blacklist are merged automatically.</li>
</ul>

Block Spammers

Block spammers from submitting comments, by IPs or by bad words.

Remove IP vs Block Spammers