Semi related: CDC (Control Data)'s Lark drive used 8" removeable platters in a plastic shell, kinda like a super-sized Jaz or Syquest cartridge. http://www.bitsavers.org/pdf/cdc/discs/lark/77738001_KS-22640_L2_LARK_Hardware_Installation_Operation_Manual_Vol1_RevA_Nov1983.pdf color photos: http://www.mbiusa.com/mbi_000043.htm