This is a (personal) list of articles dealing with unit testing that I like. I have chosen to include material that is longer than the usual (short) blog posting. I encourage readers to give more objectivity to this subjective set by submitting in the comments what they preferred ;o)
Test Flexibly with AspectJ and Mock Objects
Automation for the People: Continuous testing
Exploring The Continuum Of Test Doubles

Unit Testing With C#

End to End, or, Another Run on the Hamster Wheel of Life

In Pursuit of Code Quality: Unit Testing Ajax Applications
Apply Test-Driven Development to …

A recent Methods & Tools poll examined how organizations perform unit testing. Is it an informal activity that is done before integration if there is some time left after programming or is it the key element of the development effort? The question was: How is unit testing performed at your location?