And The Clear "Unusual UI" Winner Is ...
SequoiaView! This harddisk space manager takes a completely different approach and I found myself investigating my file system in ways I would not have dreamed without it!
The Visualization Section of the Faculty of Mathematics and Computer Science at the Technische Universiteit Eindhoven has used Cushion Treemaps, invented by Jack van Wijk, to provide an inspirational example of file system visualization. The user's selection and view is highly configurable.
Don't miss this one!