Ning and Second life

Ning is an online platform for people and organizations to create custom social networks. Ning offers customers the ability to create a community website with a customized appearance and feel; feature sets such as photos, videos, forums and blogs; and support for “Like”, plus integration with Facebook, Twitter, Google and Yahoo!.
The service allows customers to charge for membership directly within their Ning Network.Customers can also monetize by using services provided through partnerships established by Ning, and adding display advertisements,such as Google AdSense, to their Ning Network.
Ning offers 3 plans to its customers: Mini, Plus and Pro.The plans are offered with varying feature offerings and range in price so that customers can choose a plan that best fits the goal for their community.Once a plan is chosen, a customer can change it to another plan at any time. 

http://www.ning.com/

Second life

 

Second Life is an online virtual world developed by Linden Lab. A number of free client programs, or Viewers, enable Second Life users, to interact with each other through avatars. Residents can explore the world, meet other residents, socialize, participate in individual and group activities, and create and trade virtual property and services with one another. Second Life is intended for people aged 16 and over.
Built into the software is a three-dimensional modeling tool based on simple geometric shapes that allows residents to build virtual objects. There is also a procedural scripting language, Linden Scripting Language, which can be used to add interactivity to objects. Sculpted prims ,mesh, textures for clothing or other objects, animations, and gestures can be created using external software and imported. The Second Life Terms of Service provide that users retain copyright for any content they create, and the server and client provide simple digital rights management functions.