"X-Unity" -- an xUnit-like TestingFramework, intended to support ExtremeProgramming's UnitTest''''''s.

Price:  Reasonable -- $100 +

See:  http://x-unity.miik.com.ua/

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''The user interface strikes me as excessively chatty, and not set up properly to handle the *LARGE* number of tests one would expect in an XP project.  (This is my first impression, based on looking at their web site.  I'm not currently doing DotNet work.)  -- JeffGrigg''

''[Opinions from people who have actually tried this product are certainly welcome. -- JeffGrigg]''

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CategoryDotNet CategoryTesting: TestingFramework for RegressionTesting of (MicrosoftDotNet) components and applications.