DigitalTweaker

** No Longer Supported ** 
DT Author Box is great for those who have multiple authors on a WordPress site and want to show author information at the bottom of every post for each author like a signature. This can include an image, a short bio, a link to the author’s website and their social profiles.
<h4>Social Profiles Added</h4>
<ul>
<li>Twitter</li>
<li>Facebook</li>
<li>LinkedIn</li>
<li>Google+</li>
<li>YouTube</li>
<li>Pinterest</li>
</ul>
<h4>Language Support</h4>
<ul>
<li>German</li>
<li>Spanish</li>
<li>French</li>
<li>Indonesian</li>
<li>Italian – Thanks to Marco Pegoraro for accurate translation</li>
<li>Portuguese</li>
</ul>
Language translation may not be exact, Google Translate was used. If you find any errors, please let me know.
<a href="http://www.digitaltweaker.com/web/wordpress/2012/04/digital-tweakers-author-box-plugin-for-wordpress/" title="DT Author Box Plugin Home Page" rel="nofollow ugc">DT Author Box Plugin Homepage</a>

DT Author Box

Easily add an author box bio signature with custom profile image and social profile buttons to the end of each author's posts

M A Vinoth Kumar

buffercode

Comment Signature provides easy way to add user’s signature who already registered on that site.
Through this plugin user can,
<ul>
<li>Registered user can able to add their own signature on their profile.</li>
<li>Each comment will be added with signature at the bottom of comment.</li>
<li>If user not registered, no signature will be added.</li>
<li>All signatures have been <code>.</code></li>
<li>User can able to set the URL size in setting page.</li>
<li>User can able to select the font color in setting page.</li>
<li>User can add horizontal line separation width [ver 2.1]</li>
<li>User can add the margin for horizontal line to override the theme CSS [ver 2.1]</li>
<li>Admin can able to change the size of the Font [ver – 2.1]</li>
<li>Admin can able to restrict the number of characters for Signature [New – 2.2]</li>
</ul>
For more information : http://buffercode.com/project/comment-signature/
v 2.2
<ul>
<li>Admin can able to restrict the number of characters for Signature</li>
</ul>
v 2.1
<ul>
<li>User can add horizontal line separation width</li>
<li>User can add the margin for horizontal line to override the theme CSS</li>
</ul>
v 2.0
<ul>
<li>Bug fixes and support 4.2.3</li>
</ul>
v 1.3.2
<ul>
<li>Supports 3.9.1</li>
</ul>
v 1.3.1
<ul>
<li>Bug fixes.</li>
</ul>
v 1.3
<ul>
<li>Now user can able to select the font color in setting page.</li>
</ul>
v 1.2
<ul>
<li>Now user can able to set the URL size in setting page.</li>
</ul>
v 1.1
<ul>
<li>Bug fixes</li>
</ul>
v 1.0
<ul>
<li>Public release</li>
</ul>

Comment Signature

Comment Signature provides easy way to add user's signature who already registered on that site.

DT Author Box vs Comment Signature