The direct-debit form for my daughters school fees had the option for the school submitting the information via MO (Magneto-Optical) (along with paper, floppy, dvd and data transfer) https://bitbang.social/@kalleboo/111821793740460988
Sony has the worst case of not-invented-here syndrome. If they released a great mp3 player before Apple we could be living in a very different world. Instead they forced you to convert your MP3s to ATRAC.
Seems too common as a format. Better stick to Iomega Clik/PocketZip instead if you want something obscure.
No, in Japan the popular system were the magneto-optical disks.
Also MiniDisc, my car still has a MiniDisc player
Now, now... they're not that antiquated! CD-R at least... or DVD-RAM