if you have big big files you can enjoy the ability of XML::Twig to parse on the fly using twig_handler if you are smart enough you can build an handler that does everything you need as grab data and display the menu (the twig knows his father and his silbings and his children too). That said i was no able to navigate interactively an XML when i tried to do so. It would be simpler to put all the data in minimal database (SQLite)

L*