shhh! is a small XTensions for QuarkXPress 6.x.x that allows you to change style sheets in-place, without having to deal with non-interactive layers of dialogs and tabs -- just change a paragraph's attributes, click a button and "Presto-Maestro" the style sheet is modified and the whole document is updated.
as a side bonus, it will display all the differences between the original style and the current paragraph's style, effectively explaining the reason why QuarkXPress displays a "+" beside the style name in its Style Sheet Palette.
What's new in this version:
QuarkXPress 6 version (previous was for 3.1.2...) now also treats character style-sheet shows differences