I downloaded the free 8-bit music generation software FamiTracker and mucked about with it long enough to compose these three original tracks:

The program is fairly easy to use, and it's fun to make tunes that more-or-less sound like they belong in an NES game. It outputs in either .nsf (the format for NES music) or .wav, and you can even export text of your composition.

ROW 80 : A-3 02 . ... : ... .. . ... : C-2 01 . ... : 9-# 00 . ... : ... .. . ...
ROW 81 : E-3 02 . ... : ... .. . ... : ... .. . ... : C-# 00 . ... : ... .. . ...
ROW 82 : D-3 02 . ... : ... .. . ... : D-3 01 . ... : 9-# 00 . ... : ... .. . ...
ROW 83 : ... .. . ... : ... .. . ... : ... .. . ... : C-# 00 . ... : ... .. . ...
ROW 84 : A-3 02 . ... : ... .. . ... : C-2 01 . ... : 9-# 00 . ... : ... .. . ...
ROW 85 : E-3 02 . ... : ... .. . ... : ... .. . ... : C-# 00 . ... : ... .. . ...
ROW 86 : D-3 02 . ... : ... .. . ... : D-3 01 . ... : 9-# 00 . ... : ... .. . ...

...Which looks like crap outside of Notepad. But it's still a nice feature.