mdiamondstone

authorGrid is a sidebar widget that displays the avatar of any author on your blog with at least one published post in grid form. You 
can set how large the avatar should be, how many columns (or rows) you’d like in the grid, and the display title of the widget.

Author Grid

Sidebar widget that displays the avatar of all of the authors on your blog in grid form.

peterwsterling

Once the widget is added to your sidebar you may easily configure it to provide a display of recent comments with comment author avatars. The options are:
<ul>
<li>The title of the widget.</li>
<li>Limit the number of comments to shown (1 to 15).</li>
<li>Option to display the avatar of the comment author, or not.</li>
<li>Set the size of the avatar.</li>
<li>Chose to have the comment author’s URL (if given) open in a new window,</li>
<li>Show the date of the comment, or not.</li>
<li>Set the format of the date.</li>
<li>Set the size (as a fraction of the normal text size) of the date string.</li>
<li>Show an excerpt from the comment.</li>
<li>Convert smilies in the excerpt.</li>
<li>Show a country flag indicating the source of the comment, requires MySQL database modifications, see below.</li>
<li>Show a country flag in main comment loops, non-widget, requires theme and MySQL database modifications, see below.</li>
</ul>
The style of the output may be controlled with simple CSS rules that need to be included in your <code>styles.css</code> template file. 
 The container (i.e. <code><ul></code> or <code><table></code>) has the id recentcomments (use CSS <code>.recentcomments</code>). 
 List items (i.e. <code><li></code>) have the class recentcomments (use CSS <code>#recentcomments</code>).

Author Grid vs Recent Comments with Avatars