I've spoken earlier about continuous verification and how this involves running tests on a periodic basis to ensure all tests are passing. This could be during nightly builds, during check-ins using concepts such gated check-ins, or simply pressing Ctrl + R, A occasionally while coding.
There is another class of tools that performs continuous testing. This means these tools execute automated tests in the background, automatically. These tools, such as NCrunch, simply see if anything in your project changes and run all tests automatically (in the background) or, like ContinuousTests, they monitor what files are saved to disk, analyze what was changed since the last time tests were run, and only run tests that apply on the code that was changed.
These tools are great at taking the tedium out of running tests, especially when you or your team isn't using tools such as gated check-ins to make sure the code that breaks a test isn't checked-in. When you have continuous testing...