Ask HN: Your favourite outstandingly creative/informative YouTube channels?

I've learnt so far about Captain Disillusion and Every Frame a Painting from people on HN. Thank you! My favourite for years has been Vi Hart. I haven't done much youtube channel exploring at all, so no channel is too obvious. I thought I'd ask for more, seems it's been a lil while since anyone did.

So - what are your favourite art/maths/music/film/science/technology-related channels featuring makers of incredibly awesome videos? Other subjects are fine too. (Vi Hart is fascinating whatever the subject. That kind of thing.) Thanks in advance :-)

Doesn't have to be youtube.