Social Networking Websites:
www.Linkedin.com - LinkedIn is a professional social networking website for business users, one of the most popular such sites out there. Some aspects of it are free, but many are paid.
www.Facebook.com - Facebook is a social networking phenomenon connection people with their friends, family and other users with similar interests.
www.WordPress.com – WordPress is the leading free blogging and hosting site. Easy to use with many options.
www.YouTube.com – YouTube is the king of the video sharing sites, it has more users and videos than the others. Any video you can think of it probably already on YouTube.
www.StumbleUpon.com – Lets you “channel surf” the Internet and review sites; it learns what you like and recommends more of the same.
www.Digg.com Digg has a huge following online because of its optimum usability. Visitors can submit and browse articles in categories like technology, business, entertainment, sports and more.
www.Technorati.com If you want to increase your blog’s readership, consider registering it with Technorati, a network of blogs and writers that lists top stories in categories like Business, Entertainment and Technology.
www.Ning.com After hanging around the same social networks for a while, you may feel inspired to create your own, where you can bring together clients, vendors, customers and co-workers in a confidential, secure corner of the Web. Ning lets users design free social networks that they can share with anyone.
Also check out these listings:
Social Networking God – http://mashable.com/2007/10/23/social-networking-god/