Stack Exchange Employee and creator of the http://www.servicestack.net projects:

A high-performance Open Source .NET and MONO REST & RPC Web Service Framework. Including:

• ServiceStack.Redis - A fast, full-featured C# Redis Client
• ServiceStack.Text - .NET's fastest JSON and JSV/CSV Text serializers
• ServiceStack.OrmLite - A fast, lightweight, code-first ORM for SQL Server / Sqlite
• ServiceStack.Logging - An dependency-free logging abstraction w/ adapters for Log4Net, Elmah, EventLog, and Debug, Console and Null log.
• RedisWebServices - Provides JSON/XML/JSV REST web services over all of Redis operations. Includes a graphical ajax Redis Admin UI.