scibuff

If you would like to increase the exposure of your blog WordPress Connect 
it the perfect plugin for you. It comes with a unique set of tools through 
which you can reach the largest social networking community on the planet 
that would engage and then share and discuss your content. It will enable 
you to build up a fan base and to connect with a wider and a more relevant 
audience. Now your blog readers with a Facebook account can post comments, 
create discussions and like your posts and pages.
The plugin integrates Facebook Social plugins with WordPress. It provides 
tools to add the Facebook Like Button and Facebook Comments automatically 
to every post and page. Of course, the user has a full control over settings 
such as width, font, color scheme, etc.
WordPress Connect also provides fully customizable WordPress Widgets for the 
following Facebook Social Plugins
<ul>
<li>Activity Widget</li>
<li>Comments Widget</li>
<li>Facepile Widget</li>
<li>Like Box Widget</li>
<li>Like Button Widget</li>
<li>Live Stream Widget</li>
<li>Login Widget</li>
<li>Recommendation Widget</li>
<li>Send Button Widget</li>
</ul>
The widgets can be added to your blog just as easy as any other WordPress 
Widget, i.e. through the widgets page (under Appearance on your Dashboard).
Since 2.0, all WordPress Connect widgets are rendered in the XFBML mode (i.e 
no iframes) to provide full functionality the iframe versions may lack.
A big addition since 2.0 is a simple yet powerful <a href="http://wp-connect.tomasvorobjov.com/api/" title="WordPress Connect API" rel="nofollow ugc">API</a> 
for plugin and theme developers who can now specify default settings for WordPress 
Connect to reflect the needs of their plugin/theme. The API provides an easy 
way to include any widget (such as the Like Button of Comments) anywhere in 
the theme, e.g. to add the Like Button to the header or Comments to the 
footer.
Requirements
<ul>
<li>PHP 5.2.0 or newer</li>
<li>WordPress 3.0 or newer</li>
</ul>

WordPress Connect

This plugin integrates the Facebook Social Plugins with Wordpress.

yanniks

This is the Shariff for WordPress plugin based on c’t Shariff.
For more information, check out the original <a href="https://github.com/heiseonline/shariff" rel="nofollow ugc">GitHub project</a> and the <a href="http://ct.de/shariff" rel="nofollow ugc">c’t information page</a>.
<blockquote>
Shariff enables website users to share their favorite content without compromising their privacy.
Facebook, Google+ and Twitter supply official sharing code snippets which quietly siphon personal data from all page visitors. Shariff enables visitors to see how popular your page is on Facebook and share your content with others without needless data leaks.
Shariff <code>(/ˈʃɛɹɪf/)</code> is an open-source, low-maintenance, high-privacy solution maintained by German computer magazine c’t and heise online.
</blockquote>
Shariff supports sharing buttons for Facebook, Twitter, Google+, LinkedIn, Pinterest, Reddit, StumbleUpon, XING, WhatsApp and mail. 
Select which color you want, set the button location, select the orientation fitting most to your website and set the TTL just as you want.

Shariff for WordPress

Shariff enables website users to share their favorite content without compromising their privacy.

WordPress Connect vs Shariff for WordPress