Ashley

Naked Social Share allows you to insert plain, unstyled social share buttons for Twitter, Facebook, Pinterest, StumbleUpon, and Google+ after each post. The icons come with no styling, so that you — the designer — can style the buttons to match your theme.
There are a few simple options in the settings panel:
<ul>
<li>Load default styles – This includes a simple stylesheet that applies a few bare minimum styles to the buttons.</li>
<li>Load Font Awesome – Naked Social Share uses Font Awesome for the social share icons.</li>
<li>Disable JavaScript – There is a small amount of JavaScript used to make the buttons open in a new popup window when clicked.</li>
<li>Automatically add buttons – You can opt to automatically add the social icons below blog posts or pages.</li>
<li>Twitter handle – Add your Twitter handle to include a “via @YourHandle” message in the Tweet.</li>
<li>Social media sites – Change the order the buttons appear in and disable any you don’t want.</li>
</ul>
If you want to display the icons manually in your theme, do so by placing this code inside your theme file where you want the icons to appear:
<pre><code><?php naked_social_share_buttons(); ?>
</code></pre>

Naked Social Share

Very excellent, simple plugin. I dislike all the others with the loud styles.
Here's some jQuery to have a title show.
$('.nss-google a').attr("title", "Share on Google Plus");
        $('.nss-linkedin a').attr("title", "Share on Linkedin");
        $('.nss-twitter a').attr("title", "Share on Twitter");
        $('.nss-facebook a').attr("title", "Share on Facebook");
        $('.nss-pinterest a').attr("title", "Share on Pinterest");
        $('.nss-stumbleupon a').attr("title", "Share on StumbleUpon");


Very nice and clean

Simple, unstyled social share icons for theme designers.

Nolongeractive

To use the widget just drag it to a sidebar and choose one of six button styles. You can also specify a url to recommend. If you leave the url empty, the active page will be recommended.

Stumble Page Social Widget

This plugin lets you place a StumbleUpon button on your WordPress blog as a widget. You can configure the button by choosing the style and specifying  …

Naked Social Share vs Stumble Page Social Widget