What I'm listening to today: "Where do I start?", zabutom
This is a DOS FastTracker II tune from 2004 designed to push the boundaries of what is possible in tracker music. It succeeds hard, both in its chill lo-fi opening and the "impossible" middle segment (spoilers: what you are hearing is the FastTracker II executable itself, reinterpreted as PCM).
The video is posted by the original artist and contains some live commentary scribbled in the right side text field.