likeagency

This plugin allows you to add a widget with custom text, link and a FontAwesome icon. In order for this plugin to work, please make sure you already use FontAwesome toolkit in your theme.
List of features:
<ul>
<li>Choose FontAwesome icon as an image for the button.</li>
<li>Add your own text and title for the widget.</li>
<li>Select header tag for the title.</li>
<li>Customize your FontAwesome image (position, color and background color).</li>
<li>Add custom URL to use the widget as a link.</li>
<li>Add extra button displayed below, with your own text.</li>
<li>The widget has its own stylesheet included, however with just necessary CSS to be displayed properly, so it doesn’t override the style for any theme you currently use. </li>
<li>You can also add your own CSS for this plugin via its Settings page.</li>
</ul>

Button with FontAwesome icons by LIKE.agency

This plugin allows to add a widget with custom text, link and a FontAwesome icon.

Sparanoid

Adds readability.com widget on your site. A must-have plugin if you’re a Readability publisher. This plugin also works fine with multisite enabled WordPress (aka. WordPress Mu).
More information please visit my <a href="http://sparanoid.com/work/readability/" rel="nofollow ugc">site</a>.

Readability Buttons (readability.com)

Adds readability.com widget on your site.

Button with FontAwesome icons by LIKE.agency vs Readability Buttons (readability.com)