Founded: 2000

Estimated users: 105 million to 200 million (reportedly)

Addictiveness rating: 9.5

MySpace has been undisputedly the number one social networking site and was brought in July 2005 by News Corporation, the company owned by Rupert Murdoch. A major feature of MySpace is the way that it allows musicians to get their songs to the public and build up a fan base without the need for a record label or radio airtime. The Arctic Monkeys and Lily Allen both shot to fame via MySpace.