Festalon is a very accurate NSF(NES Sound Format) player. All of the basic sound channels are emulated, and support exists for extra sound channels as found in the VRC6, VRC7, MMC5, FME-7, Namco 106, and FDS(partial). CPU requirements are a bit high. You'll probably need to have a processor that can perform integer math at or greater than the speed of a Pentium II 266MHz CPU, and something a little faster if extra sound chips are used, especially the Namco 106 and FDS.
Listen to all the golden musical hits from the original 8 bit Nintendo Entertainment System. NSF files are especially cool in that you can isolate different instruments (bass, lead, percussion, etc.).... which can come in really handy for producers who like sampling. It's amazing how
some of these NES songs can really trigger memories from the mid to late 80's; anyone who gamed during the 8 bit times should download this for sure. You may have to do a little digging around the net for the .nsf files, but, they are out there.