Sinclair QL filesystem

The filesystem used by the Sinclair QL (a 1980s computer system) was originally used on a microdrive cassette, then a modified version was later stored on 3.5" floppy disks of the same physical format as the PC-DOS 720K disk, apparently with the sectors interleaved in a different order.

Links

 * A description of its format
 * Other Sinclair QL info