I'm looking at the workflow between developer, tester and CI server to come up with an approach for maintaining environmental specific settings (local dev box, dev/test environment, qa environment, production) such as:

Base URL
Username / Password by Actor / Role
Key Data Values 

I see a number of disconnected techniques such as the VS test settings file, data sources, and test list settings.  There seems to be a lack of a universal "project file" across the tool sets which doesn't help either.  What I would like to be able to do is:

Developer - selects a "settings/parameters file" in Test Studio Express with environment parameters
Tester - selects a "settings/parameters file" in Test Studio Standalone with environment parameters
Build - execute runner with a specific "settings/parameters file" that contains environment parameters

Within the test then I can say "Navigate to {BaseUrl}/Reports", "Login as {Regular User}", etc... I want to do this without having three types of files per environment.