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.

output48

When you added new post, this plugin send email to Hatena bookmark.

Hatena Bookmark AutoPost

When you added new post, this plugin send email to Hatena bookmark.

WP Social Bookmarking Light vs Hatena Bookmark AutoPost