The Onlywire multi autosubmitter is a free WordPress social bookmarking plugin. It can be installed easily on all WordPress weblogs and allows you to submit all your posts to many different social bookmarking and networking websites, including Digg, Reddit, delicious and Mixx, through the Onlywire social bookmarking service automatically.
Requiremments:
Demo Weblog: http://demo.lunaticstudios.com/
Plugin Homepage: http://lunaticstudios.com/software/wp-onlywire-multisubmit/