Babak Fakhamzadeh

This plugin allows for custom avatars. In the backend, a custom avatar can be uploaded for a user in the user-edit form. In the frontend, an upload form, for the current user, can be shown by using the shortcode [mb-simple-user-avatar].
<h3>Instructions and Usage</h3>
<ul>
<li>Shortcode</li>
</ul>
[mb-simple-user-avatar]
The frontend upload form is only available to the current user, when logged in.

MB Simple User Avatar

I am enhancing my system more and more and don't want complicated plugins. I use now yours with clean Login which functions best on users Edit page. I tested several plugins but yours is the best as I wanted it on frontend :)

But I miss that this picture is also to see by commenting posts.

Simple is the best

A plugin allows for custom avatars. In the backend through the user-edit form, in the frontend through a shortcode.

Dougal Campbell

This plugin allows you to automatically add Gravatars for commenters to your 
theme, if your theme does not already support them.
According to the Gravatar.com website, Gravatars are Globally Recognized 
Avatars, or an “avatar image that follows you from weblog to weblog 
appearing beside your name when you comment on gravatar enabled sites.” 
You register with the Gravatar server, and upload an image which you will 
use as your avatar. The gravatar image is keyed to your email address, so 
that it is unique to you.
This plugin will display gravatars for the people who comment on your posts. 
You do not need to modify any of your template files — just activate the 
plugin, and it will add gravatars to your comments template automatically.
<h3>Credits</h3>
Based on a code snippet from Matt Mullenweg: 
 http://photomatt.net/2007/10/20/gravatar-enabled/ 
 http://pastebin.ca/743979
Props to David Potter for pointing out that Gravatar normalizes email 
addresses to lowercase before hashing with MD5: 
 http://dpotter.net/Technical/index.php/2007/10/22/integrating-gravatar-support/

Easy Gravatars

nice

Add Gravatars to your comments without modifying any template files. Just activate, and you're done!

MB Simple User Avatar vs Easy Gravatars