Adlib (OPL)
* Adlib Tracker II (.a2m)
* AMusic_v1.12 (.amd)

Atari XE/LE
* RMT_v1.25 (.sap)

Commodore_64 (.sid)
* DMC
* Goat Tracker

GameBoy
* BoyScout_(Win32) (.bgf)
* Carillon editor (GB*/GBC*) (.???)
* LSDJ (GB*/DS) (.sav)
* Paragon5 (GB*/DS) (.mgb)

Mario Paint (.sho)

NES Famicom (.nsf)
* FamiTracker
-- FamiTracker_Effects_Commands
* NerdTracker II
* PPMCK (Not a tracker...)
* NesTracker
*** NTRQ (hardware tracker!)


PandaTracker

s3xmodit
* FastTracker II (.xm) DOS
-- FastTrackerII_Effects_Commands
* MilkyTracker (.xm) multi-platform
* ImpulseTracker (.it) DOS
-- ImpulseTracker_Effects_Commands
* SchismTracker (.it)
* ChibiTracker (.it) windows clone


Sinclair ZX Spectrum
* Vortex Tracker (.ay)
* TFM Music Maker (.vgm, OPL2 FM expansion chip)

SEGA Master System (.vgm)
* MOD2PSG2

VIC_20
* Vic_Tracker (.vt)

Helper tools! =o
* BoobieSqueezer (XM optimizer)
* it2nsf (converter, not a tracker)
-- OpenSPC can convert from SPC files to .IT
* s3m2nsf (converter, not a tracker)
* ShroomTool (Mario Paint song data extractor)


-- please add more to this list (keep it alphabetically ordered) --