I'm trying to devise an icon to indicate that when it is clicked, it will collapse all the nodes in a tree. The tree contains profiles which already have an icon, so ideally I'm looking for a "decorator" for our profile icon (like the star-burst used to indicate that clicking this button will create a new thing, or the pencil that indicates that clicking the button will edit the selected thing).
I've tried using the Windows tree node icons, but these are hard-coded to the Windows Vista/7 style and so will look wrong on Windows XP; also, given that they are triangles, they're a bit abstract.
UPDATE: The icon will be displayed in a separate "Actions pane" to the right of the tree view.