A free and open source unit testing tool for the .NET Framework
Editor: csUnit is a free and open source unit testing tool for the .NET Framework. Unit testing is tightly associated with test-driven development (TDD), refactoring, and other practices from agile software development approaches such as Extreme Programming or Scrum.

Major Features

* Standard unit testing features such as test, fixture, setup, teardown, ignore, expected exception, etc.
* Easy to use graphical user interface
* Recipes for combining several test assemblies into one test suite
* Addin for Visual Studio 2005 and Visual Studio 2008
* Executes tests based on the following frameworks:
o csUnit
o NUnit (version 2.4.7, .NET 2.0)
o Microsoft unit testing (basic support, VS 2008)
* Search capabilites across tests, output, and statistics
* Statistics per test to Create performance base line
* Categories to group tests for Execution
* Support for applications targeting .NET 2.0, .NET 3.0, and .NET 3.5
* Works with any .NET language (C#, VB.NET, Managed C++, etc.)
* Runs on Windows Vista SP 1 or Windows XP SP 3 you can free download csUnit 2.6 now.