Jayrock

Jayrock is a modest and an open source (LGPL) implementation of  JSON and JSON-RPC for the Microsoft .NET Framework, including ASP.NET. What can you do with Jayrock? In a few words, Jayrock allows clients, typically  JavaScript in web pages, to be able to call into server-side methods using JSON as the wire format and JSON-RPC as the procedure invocation protocol. The methods can be called synchronously or asynchronously.

Go to http://jayrock.berlios.de/

See also these related projects.