QMK song player is a
web app that reads QMK song code and plays it in your browser.
If you have a QMK keyboard with a speaker, you can use the audio
feature to produce these songs from your
keyboard (how to add songs to your
keymap).
Why do this? Because it is fun! You can play a song when the keyboard starts up,
or more functionally, play a little melody to indicate events like when setting
the default layer.
QMK comes with a good number of predefined songs out of the box. Here are a
couple to whet your appetite:
Yes to combat music, excellent idea! If you can play it by ear or find sheet music for it, it can potentially be coded note by note in QMK song syntax.