Json.NET is a popular high-performance JSON framework for .NET
-Flexible JSON serializer for converting between .NET objects and JSON
-LINQ to JSON for manually reading and writing JSON
-High performance, faster than .NET's built-in JSON serializers
-Write indented, easy to read JSON
-Convert JSON to and from XML
-Supports .NET 2, .NET 3.5, .NET 4, .NET 4.5, Silverlight, Windows Phone and Windows 8 Store
Documentation:
http://james.newtonking.com/projects/json/help/
