I am happy to announce the first public unveiling of my Fox in a Box project. The enthusiasm for my idea of putting together a dev VM was loud and clear in my last post, mainly from testers who expressed interest in hunting regressions at a more granular level. The README in the first link hopefully contains enough details for anybody to get themselves set up with a minimal Ubuntu 11.04 VM with a preset clone of mozilla-central ready to build. I experienced clobber build times of 30-45 minutes in my tests; your mileage may vary. So please, run
$ git clone git://github.com/jdm/foxinabox.git, follow the README and let me know how it goes for you!