Sort all posts by modifed time?

Is there a method that would allow the sorting of a post on any page (regardless of category) that would sort not by the created time but by the modified time? Is this something that requires a plugin and some hacking or modifying current pages?

I tried this code and it did nothing:

<?php query_posts($query_string.”&orderby=the_modified_time=ASC”);
if (have_posts()) : while (have_posts()) : the_post(); ?>