So far, there are two I've found:
- Feldhellschreiber - an on/off fax like transmission of letters using 1ms dots
- CCW - "Coherent CW": an accurately timed version of morse with extra characters supported by MultiPSK. It runs at 12 words per minute and includes a start sequence to allow synchronisation.
- Any others?
There's an informative thread in the Yahoo? digitalradio group.