rafafc

Display and follow the conversation on social media (Twitter, Instagram and many more) about a #hashtag on your site.
Watched social net is a plugin that allows you to put together all your social media content (including #hashtags, 
@accounts, videos, photos, and tweets) in an amazing social wall on your WordPress site. Watched will automatically 
display the post via hashtag on screens of any size. We support hashtag conversations from Twitter & Instagram.

Watcher Social Net

Display and follow the conversation on social media (Twitter, Instagram and many more) about a #hashtag on your site.

utahta

This plugin inserts social share links at the top or bottom of each post. 
For theme developers, social share links can be added by PHP code or by using shortcode. Check documentation for this use-case.
This plugin documentation can be found <a href="https://github.com/utahta/WP-Social-Bookmarking-Light/wiki" rel="nofollow ugc">here</a>.
This is the list of used social sites:
<ul>
<li>Hatena</li>
<li>Facebook Like Button</li>
<li>Facebook Share Button</li>
<li>Facebook Send Button</li>
<li>Twitter</li>
<li>Tumblr</li>
<li>Google Bookmark</li>
<li>Google +1</li>
<li>Delicious</li>
<li>Digg</li>
<li>reddit</li>
<li>LinkedIn</li>
<li>Instapaper</li>
<li>StumbleUpon</li>
<li>mixi Check</li>
<li>mixi Like</li>
<li>GREE Social Feedback</li>
<li>atode (toread)</li>
<li>LINE</li>
<li>Pocket</li>
<li>Pinterest</li>
</ul>

WP Social Bookmarking Light

This plugin inserts social share links at the top or bottom of each post.

Watcher Social Net vs WP Social Bookmarking Light