Andreas Grabs came across this when converting Feedback to Moodle 2.0.
He wants to let the feedback module create templates an template items that can be used across a course or site. These template items have texts that might contain media, so they need a filearea and context.
1) If the filearea is tied to any specific feedback instance, then feedback_pluginfile() is called and can handle permissions, but then the templates will be DELETED whenever that instance is deleted.
2) If a new course-level filearea is created for them (eg feedback_items), then pluginfile.php will not be able to serve them (and will not know how to find mod/feedback/lib.php to call feedback_pluginfile()).
What is the best solution for these cases?
One might be to extend pluginfile.php to handle module-created fileareas at course level or system level.