Eclipse 2.0 has integrated support for JUnit. The org.eclipse.jdt.junit plugin supports launching JavaUnit tests from Eclipse and to view the test results. 

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	* Create a test suite for a specific class, and select which methods should have tests stubbed in.
	* Junit results and controls integrated directly in Eclipse
	* Click on a test to open editor to that test, click on stack trace to view appropriate
	* Auto create test suites for a given package
		* ''Unfortunately, you have to put in a call to each package's suites to make a master suite, but seeing as one generally creates many more classes than packages, it's not too bad.''
	* Rerun individual tests when run in debug mode
	* Test case wizard will automatically add code to allow stand alone running of test cases in Swing, AWT or text modes
	* (not quite what all else they're putting in, it's still in a functional 'preview' release) 
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EclipseIde supports parallel source folders, making it quite easy to separate tests from production code without messing around with packages. Only real problem I have with it is that it doesn't automatically add a new test case to the package's test suite, even though eclipse will regenerate the suite with the appropriate case added on request ('Recreate Test Suite'); really a minor issue though, I'm quite happy with the integration they've done. -- WilliamUnderwood
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In the 2.1 development stream the JUnit plugin can find and run all tests inside a package, source folder or project.
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It would be nice if the JUnit plugin could search for classes using a name filter (like in Ant). That way we could specify *Test to find tests. As it is now, if you subclass TestCase to make project specific additions (clean up or common meaningful asserts) you will get a warning that the subclass has no tests in it. This happens even if the subclass is in a different source folder than the tests.

A workaround would be to unwrap Eclipse's junit.jar to add entries to excluded.properties and wrap it again. But that seems like a lot of work to do every time you want to subclass TestCase. And it certainly is not project specific...