On Tue, 18 Nov 2003, J.C. Wren wrote:
          A starting point is: 
  8080:
        Electric Pencil  (had its own file system before CP/M)
        CP/M
  Z80:
        CP/M (and variants: MP/M, etc)
        TRS-DOS 
          APR-DOS
                NEWDOS
                DOSPLUS
                VTOS
                LDOS
        MicroDos (Micropolis)
        UCSD P-System
  6502:
        Apple DOS 
                PRODOS / SOS?
                Apple Pascal (UCSD P-Syatem)
          Commodore DOS (not sure of the name) 
Atari
  6800:
        Flex 
  6809:
        Coco RSDOS   (NO relationship to Z80 TRS-DOS other than owner and
name)
        OS-9
        Flex?