The popular (and addictive) Question and Answer Site Quora is not just a hobby. There are many people earning serious money with it.
Affiliate Marketing
This guy earns money by including affiliate links into his answers. Read his excellent Quora answer to learn more about this way of earning money with affiliate links.
Deal Flow
Watch Gordon Miller at Quora. He is crushing it. He doesn’t earn direct money from Quora but as an investor, he is constantly searching for new deals. Quora gives him deal flow!
Quora Partner
This Quora user was invited to become Quora partner. The earnings are quite limited though—but read yourself:

While working as a researcher in distributed systems, Dr. Christian Mayer found his love for teaching computer science students.
To help students reach higher levels of Python success, he founded the programming education website Finxter.com that has taught exponential skills to millions of coders worldwide. He’s the author of the best-selling programming books Python One-Liners (NoStarch 2020), The Art of Clean Code (NoStarch 2022), and The Book of Dash (NoStarch 2022). Chris also coauthored the Coffee Break Python series of self-published books. He’s a computer science enthusiast, freelancer, and owner of one of the top 10 largest Python blogs worldwide.
His passions are writing, reading, and coding. But his greatest passion is to serve aspiring coders through Finxter and help them to boost their skills. You can join his free email academy here.