Wikipedia
MetaFilter
MetaFilter, known as MeFi to its members, is a general-interest community weblog, founded in 1999 and based in the United States, featuring links to content that users have discovered on the web. Since 2003, it has included the popular question-and-answer subsite Ask MetaFilter. The site has six paid staff members, including the owner, and, as of early 2011, about 12,000 active members.