The inline searching seen in the 10.5 Help menu could be used in other menus.
Providing searching in the Bookmarks menu in browsers and the menu immediately right of the Application (File/Document/Thingamajig) would also make sense. The default search scope would be filetypes the application can open or import.
This type of inline searching would provide the sort of application-specific search focus that I mocked up earlier, but it doesn’t provide an easy way to move a query between applications.
Yes, jazz bagpipes. That cat could burn!