UI conventions for NSPredicateEditor

I'm aware of bare bones sample / tutorial implementations of NSPredicateEditor:

http://developer.apple.com/library/mac/#samplecode/PredicateEditorSample/Introduction/Intro.html

The only places I've seen UI resembling a NSPredicateEditors in real applications are the Smart Playlist form in iTunes and the photo filter form in Aperture. I'm curious about conventions for:

• Placement of a NSPredicateEditor in relation to a table view.
• UI to hide and reveal the NSPredicateEditor.
• Buttons (if any) to apply the predicate.

What are other examples of effective implementations of NSPredicateEditor in real applications?

cmd-f in Finder will bring up an advanced find window, which features a predicate editor with an accompanying tableview.