Bracket View for Nautilus Browser

Just stumbled across this on gnome-look.org. I think it's really nice and exactly what Nautilus could do with, to differentiate it from the pack. I've always wanted a column view in Nautilus, but this idea goes one better... I think the easiest way to implement something like this would be to program a GObject with almost exactly the same API as GtkTreeView and adapting the current Nautilus list view. Perhaps Ross's OwlTreeModelSlice could help here?

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