I think you’re going to struggle with that topic, if only because it’s a played out one. Just off the top of my head I can think of online teaching and a recruitment agency, but they’re both largely scams. Topics could also include skills (writing university essays for students), but that’s also low pay in an already saturated market, or consultancy work. In other words, if someone found a way to make a decent living online they wouldn’t be broadcasting it to the world and so what you’re left with is advertising revenue and I doubt you’re going to make any standard of living from that.