Disk objects (WPDisk class, i.e. the objects in the &link_drivesfdr;) support the following codes in addition to the codes for all objects:
$fX
free space on the drive
$zX
total size of the drive

In the above two, X is a special format specifier character.

$F
file-system type (FAT, HPFS, JFS, CDFS, ...)
$L
disk label

Notes:

The $f and $z codes are redefined for disk objects. Normally, they display the space on the drive on which the folder resides, which, for the "Drives" folder, would of course always return the same value for the drive on which your Desktop resides. Thus this code has been redefined for drive objects.