As I said earlier, this HOWTO doesn't cover the Series 3 ( e.g. 3/3a/3c/3mx/Sienna ), however, as I run into information, I will try to place it here anyway. This section will probably never be organized (unless someone else keeps it uptodate), but it still might contain useful information.
p3nfs, referenced above mounts the psion drives over the serial cable at /psion.stand/mnt, by default.
nfsc is a vt100 emulator.
Zerlegeanleitung Psion Serie 3a