TiMidity plays MIDI and Module (.MOD) files. It does it in software without depending on any hardware MIDI support your soundcard might have. Sound quaility can be much higher because it limited by your CPU's power and memory rather then your soundcard's power and
memory.
Update
Dec 11th, 2001: Another update to TiMidity MCD 2.10.4. Fixes:
Will now work with TIMIDITYDIR to allow the timidity.cfg to be somewhere other then
C:TIMIDITY.
If the audio device is in use it will now return a proper error message.
Debugging symbols successfully stripped from dll.
Updated documention on the timidity.cfg file.
http://www.reamined.on.ca/doconnor/timidity.html
Source: