This thread's full of really valuable information, so I've compiled these and a bunch of the other courses mentioned here into a big document[1]. I've also added quotes from this thread, with links back to the original comments.

[1] https://www.notion.so/MOOCs-recommended-by-Hacker-News-e1070...

EDIT: the previous link pointed to one of the headers in the page, instead of the page itself.