DOS (1995 - 1997):

FastTracker ][


Windows 95/98 (1997 - 2001):

modplug tracker
cooledit '96 (no longer available)
rebirth


Debian GNU/Linux (2001 onwards):

Puredata
Soundtracker
Cheesetracker
modplug tracker (under wine)


Some software I wrote:

Looper Advance
aSid (Commodore64 program)