Regression testing with PEX

A new project from Microsoft research, PEX is an smart tool integrated directly into Visual Studio which helps you generate test suites with max code coverage.  It analyzes your code and suggests various arguments to ensure all paths of your code are tests.  These arguments and return results can then be turned directly in to .NET test methods either using the standard VS Test framework, or NUnit/MBUnit via extensions.

Also recently released is another free testing tool NP .NET Profiler, which can be hooked into .NET processes such as IIS to monitor memory and performance bottlenecks as well as catch first chance exceptions.  This low impact tool can be used in production environments and even has its own query interface for getting to the heart of problems.