Had someone recommend me this program the other day and it's pretty fun to play around with. Basically it's a normal MIDI player (not an editor) that emulates the sound of 8-bit video game consoles and is completely free to use (I believe development stopped on it a while ago and it's still in beta phase)
"GXSCC is a quite unique MIDI player to support MID/SMF/RCP formats. It doesn't depend on sound devices, plays with emulating SCC sound chip which once had been embraced as an external module for Konami's MSX cartridges like Nemesis II. It follows that all MIDI songs are changed to chiptunes!"
Basically it turns this:
(note: this is not the original MIDI)
(the 8-bit type sound is best heard at 2:25 (when percussion and backgrounds come in)
Of course unlike Fami-tracker, you can't mess with the instruments values like volume and noise (also it auto-chooses instruments based on the MIDI instrument) but it's really easy and quick to use (it has a publishing option).