Plugin jSocial — WordPress.com

JSocial free edition is a light-weight WordPress plugin that adds a floating bar to your site to get you maximum shares.

Responsive, Customizable and Extensible
WordPress Optimized
Easy to understand and to read
A Quality Set of Buttons
Each social provider can be enabled or disabled (Selective disable)
Sharing with Facebook, Twitter, Google+, Delicious, Pinterest, Stumbleupon and Linkedin *Only in Premium Version
Super lightweight social sharing
Easy to use and integrate
Massive Exposure
Make it Easier for your Users to Share your Content
Custom Placement
And much more!

jSocial