I got to love the workflow "drush make" gives us. I am sure there are others who would want their development code to be put into a make file with it not being ready for drupal.org, for example, deploying a new development testing instance of the site quickly with a bash script or from what I have seen in Aegir.
It seems the current workflow that may suit this would be to utilize a git repository of your development code. However, my development machine is Windows 7, and I would like to use "drush make" in a virtual box with an Ubuntu server instance.