I pretty much like the list here: http://www.smartdogservices.com/oracle-applications-integrations/ords-use-case-integrating-salesforce-com-customers-ebs/
Seems pretty comprehensive. Although from my experience the following request headers ONLY work with the RESTful services which you define in the APEX sql workshop, NOT in the ORDS 3.0 repository:
But you can retrieve them directly from owa_util.get_cgi_env(). They are just called differently there. But with owa_util.print_cgi_env you can see all available variables.
The x-apex-status and x-apex-forward response headers still work in the ords repository.
Hope that helps,
I checked this page out a while back when first exploring ORDS and had forgotten (or hadn't realised the significance of) the bind variables mentioned there. Thanks for redirecting me there.