The best universities in the world make their courses available online for free - what a time to be alive! I wonder if it's still possible to make money selling online courses in CS.
Lots of scammy-looking FANG Algo/Career sites sell subscriptions and seem fairly lucrative, and then you have Udacity/Coursera/Edx that sell you a certificate if you want one. Personally I quite like Udemy because they’re cheap and very specific - a lot are junk but some are really good (like the Stephan Girder series on JavaScript and docker).
