I think that facets (primarily Web facets but there are probably others) are almost as relevant candidades for pre-defined search scopes as modules are. Personally I could imagine replacing the Module radio button + dropdown in the Find in path dialog with a Module/Facet radio+dropdown.
Background story: In IDEA 4.5 we used a separate module for our JSP files to get an easily accessible search scope. With IDEA 7 there is just one module with a Web facet, and we have to specify a custom search Scope which then ends up at the bottom of the Custom scope dropdown which requires scrolling to be found. This very often used option should be more easily accessible IMHO.