Digg

 Website: http://digg.com – founded by Kevin Rose in Nov 2004, San Francisco, CA – see also the podcast http://diggnation.com

Digg is a place for people to discover and share content across the web, from the biggest online destinations to the most obscure blog. Digg surfaces the best stuff as voted on by our users.

Every article submitted to Digg has a count of how many Diggs the story has received. You need to be signed-in to Digg a story. For every registered user that clicks “Digg it” the count goes up one. If a story reaches the tipping point, then it gets promoted to the homepage.