blink, StumbleUpon, Propeller, Digg, these are best bookmarking, social book tools can be used, socialmarker .com
Social bookmarking allows users to submit a website url to their list. The website url is then viewable on their website and will start receiving traffic almost immediately. There are many different social bookmarking website, from digg.com which is mostly article related, to del.icio.us which is pure url. Submitting multiple times and extensions of the same url to these websites can be considered spam, but one submission is fine.