Since the release of this module there are now new ways to do this. Please don't use this module unless you're willing to maintain it, if that's the case, please contact me.
This module started from the idea to be able to 'record' a feature. Well, not the entire feature of course, but parts of it that are hard to backtrack when you started creating the feature. Even more specific: the strongarm part of a feature. If you want your feature to be truly 'activate module and go'-style, strongarm is simply unmissable.
What variable was changed during the creation of a feature is really hard to track. You'd have to inspect all the form elements to see how the variable could be named. Could be, meaning that you do not get the correct variable name by just inspecting form elements. Multiple elements could be stored in one variable etc. As an extra option, you can also track changes to permissions and export them too.
An overview of both the variable changes and permission changes will be supplied when the recording has stopped. You can easily select what changes you would like to be exported or not.
Beta
Currently this module is in beta (don't we all love beta?) and will only export 'changes' to a .info style format for use with drush.