It's closely based on the 4-disc Lord Of The Rings DVD packaging which I liked at the time.
Disc 1 was to contain the Special Edition.
Disc 2 would have the theatrical cut and possibly the extended edition - though I loathe that version.
Disc 3 would have behind the scenes documentaries and so forth
Disc 4 would contain updated versions of Cryo's DUNE and Westwood's DUNE 2 (Dune 2000)
and there was to be a booklet with "pop-up" elements!
It's all a bit out of date now, so have started revamping the design for Blu-Ray!