The patent was on the nested menu style of media organization. So that familiar artist/album/genre drill-down UI that the original iPods had and made them so fa

The patent was on the nested menu style of media organization. So that familiar artist/album/genre drill-down UI that the original iPods had and made them so famously usable. I don't know of any direct prior art, since apparently a slightly different form factor yields patent protection. If I recall, the Creative product was the first to do this on a mobile device, however it was a familiar media access technique for a number of players on computers, including Winamp.