KRISÚ

The Custom Share Button Plugin is a simple WordPress plugin that allows users to share posts via a custom share button.

Custom Share Button

A simple plugin that allows sharing posts via a custom share button.

Sparanoid

Adds readability.com widget on your site. A must-have plugin if you’re a Readability publisher. This plugin also works fine with multisite enabled WordPress (aka. WordPress Mu).
More information please visit my <a href="http://sparanoid.com/work/readability/" rel="nofollow ugc">site</a>.

Readability Buttons (readability.com)

Adds readability.com widget on your site.

Custom Share Button vs Readability Buttons (readability.com)