Goran Petrovic

This utility plugin allow you to bookmark your site in admin bar.
This plugin is very useful if you have several, local or online, WordPress instalations.You can set up all sites admin bar, from one point.
So, you can jump fast from WP admin to WP admin.
Features
<ul>
<li>Fast jump from WP to WP </li>
<li>Global register sites</li>
</ul>

WP Jump

sherman-snow

This plugin adds a set of cool icons and widgets at the end of your post for your readers to share. Widgets are Twitter, Facebook and Google +1. It supports large icons and small icons.
Info : http://wordpress-plugins.us/special-social-sharing-icons-4/
<h3>Changlog</h3>
1.1 Fix bug and added information about plugins
1.2 Tested 3.4.1 
1.2 fix activate error 
1.3 Tested 3.4.2

Special Social  Sharing icons

Adds a set of cool icons and widgets at the end of your post for your readers to share. Adds more new icon....

WP Jump vs Special Social Sharing icons