digg

"The site's main function is to let users discover, share and recommend web content. Members of the community can submit a webpage for general consideration. Other members can vote that page up ("digg") or down ("bury"). Voting takes place on digg.com, plus many websites add "digg" buttons to their pages, allowing users to vote as they browse the web. The end product is a series of wide-ranging, constantly-updated lists of popular and trending content from around the Internet, aggregated by a social network." wikipedia