Social Bookmarking Links
Some of our web pages includes links to various social bookmarking websites, which allow you to tag and share links with friends and others with similar interests.All of these sites are free to use but do require you to register first.
Wikipedia article on social bookmarking
For more details about each of these services:
Del.icio.us
To register: http://del.icio.us/register
More information: http://del.icio.us/about
Digg
To register: http://digg.com/register
More information: http://digg.com/about
To register: http://reddit.com/login
More information: http://reddit.com/help/faq
To register: https://register.facebook.com/r.php
More information: http://www.facebook.com/about.php
StumbleUpon
To register: http://www.stumbleupon.com/sign_up.php
More information: http://www.stumbleupon.com/about.html