I'm using Rails Devise[1] for user auth, and http basic auth for RSS. RSS Basic auth credentials are always auto-generated, and don't give access to anything other than fetching the RSS feed.
Rails uses the "master key" to let you check in encrypted database credentials. I don't use that but Rails still requires a key for deployment--so I just checked in a key. Rails is really designed for a codebase that matches to a single deployment so this is a bit of a workaround.
Also the author checked in a credentials and a master key to github