My favourite is to create them and link them, but host them from an internal server so that no one external can access them (eg hosting it at http://internal.ex

My favourite is to create them and link them, but host them from an internal server so that no one external can access them (eg hosting it at http://internal.example.com/source.map http://internal.example.com/source.map) - so if anyone tries to load it, either the dns won't resolve or they won't be able to access the server.