I''ve been lurking on the list for a few weeks now, as well as working through the Agile book and the Wiki, and I''ve run across several detailed discussions about authentication/authorization (A/A: includes login, permissions, ACLs, etc., etc.). I''ve been particularly struck by the apparent consensus that it''s impossible to design a general-purpose A/A plug-in for Rails or web apps more generally. That''s bad news, as I would love to benefit from the work of somebody smarter and better-educated about A/A and Rails than I am :-) I have to work up an A/A strategy for a new web app project, and I''m wondering if people have any suggestions for higher-level tutorial resources on A/A? What I have in mind is not one more plug-in or a ruby/rails code tutorial, but a more conceptual discussion of how to think about A/A needs and tradeoffs when designing a site, design patterns that work for particular domains of A/A problems, and what to think about when designing a web-app permissions system for scalability, extensibility, performance, etc. Anyone got favorite books, articles, other resources that they can recommend? tia, --CJ