可以内置到.NET环境中的单元测试工具TestDriven.NET

TestDriven.NET是一个VS.NET单元测试工具，它能够与VS.NET 2003环境完全集成。它应该算是在NUnit的基础上编写的一个工具，测试代码的语法与NUnit相同。官方网站为http://www.testdriven.net/ 。下面是其官方介绍：
TestDriven.NET makes it easy to run unit tests with a single click, anywhere in your Visual Studio solutions. It supports all versions of Microsoft Visual Studio .NET meaning you don't have to worry about compatibility issues and fully integrates with all major unit testing frameworks including NUnit, MbUnit, & MS Team System.
据说VS.NET 2005版本内置了单元测试功能，不知道效果会如何，等待其正式版本中。