sandbox for testing application I have developed an application and I want to test it in a fresh environment (e.g. as if this is a clean OSX, no custom /usr/local, a fresh ~/Library, etc.). What would be the simplest way?
Since Lion it is possible to run a virtual copy of Mac OS X on Apple hardware (e.g., with VirualBox, Parallels, VMWare).

You could install a clean copy, take a snapshot and use this fresh installation for tests.