DoMelhor for Sociable

Automatically add links to your favorite social bookmarking site on your posts, pages and in your RSS feed. WordPress 2.6 or above and Sociable 3.4.1 or above is required, if you use an older version of those, please upgrade.

More info:

• More info on Sociable, with info on how to add sites to it, and how to integrate it into your WordPress in other ways.
• Check out the other WordPress plugins by the same author.
• Also at iPublicis4Wordpress.