Browsing of tree structures using Miller columns has a fairly long tradition. Think Smalltalk's code browser: http://www.pharo-project.org/about/screenshots ht

Browsing of tree structures using Miller columns has a fairly long tradition. Think Smalltalk's code browser: http://www.pharo-project.org/about/screenshots http://www.pharo-project.org/about/screenshots Or NeXSTEP where you see the Cocoa ancestry for this columnar display: http://en.wikipedia.org/wiki/File:GNUstep-liveCD.png http://en.wikipedia.org/wiki/File:GNUstep-liveCD.png Beyond Finder, you'll notice that on your iPhone / iPad this paradigm is everywhere. When you see a list, you can select an item and dive into the next level. The only difference is that a single column consumes the entire screen width. See UINavigationController: http://developer.apple.com/library/ios/#documentation/uikit/reference/UINavigationController_Class/Reference/Reference.html http://developer.apple.com/library/ios/#documentation/uikit/... In Cocoa, there is a general NSBrowser class, which implements this paradigm: https://developer.apple.com/library/mac/#documentation/Cocoa/Reference/ApplicationKit/Classes/NSBrowser_Class/Reference/Reference.html https://developer.apple.com/library/mac/#documentation/Cocoa... Another application that uses faceted browsing is of course iTunes: http://screenshots.oahermes.com/6/large_4_itunes_store.png http://screenshots.oahermes.com/6/large_4_itunes_store.png One project which I tracked long ago, called mSpace, has some good stuff: http://research.mspace.fm http://research.mspace.fm