I recently discovered Audacity includes plug-ins for audio separation that work great (e.g. split into vocals track and instruments track). The model it uses also originated at Facebook (demucs).
Audacity is very very very far from state of the art in that respect.
> for audio separation that work great
What did you compare it to? Ableton recently launched a audio separation feature too, and probably the highest ROI on simple/useful/accurate so far I've tried, other solutions been lacking in one of the points before.