Diana K. Cury

Very simple pluing, no configs, no screens, just action! 
Simple Smilies add all WordPress smillies in comments form and a simple javascript let users click them to insert. 
This is a very light plugin, the javascript only loads when in singular/single contexts, also there is no stylesheets.

Simple Smilies

Let users insert WordPress smilies when commenting in you site.

Ricardo Gonzalez

Smilies Themer allows you to use smilies (emoticons) themes (or packs) to replace the wordpress default ones.
View page plugin for more info.
Features
<pre><code>* Works (with WP 2.2+)
* Compatible with More Smilies themes
* Options page
* Multilinguage support
</code></pre>
Usage
No user interaction needed. Just activate the plugin, select a smilies theme and profit!
For more info (themes, translations, etc.) visit <a href="http://rick.jinlabs.com/code/smilies-themer" title="Smilies Themer" rel="nofollow ugc">the plugin homepage</a>.
Credits
Matt Read – The plugin is a a crop of his More Smilies (now unsupported), so the major part of the credits goes to him.
License
This plugin is released in a GPL license.
Contact
Suggestion, fixes, rants, congratulations, gifts et al to rick[at]jinlabs.com or by my contact page.

Smilies Themer

Smilies Themer allows you to use smilies (emoticons) themes (or packs) to replace the wordpress default ones.

Simple Smilies vs Smilies Themer