Multi-vendor marketplaces, like ThemeForest, can be very successful. Chose a niche and create a vendor website for it. Your marketplace could be anything, from a platform for local artists to sell their work on, to an online digital product store. Once set up, invite people in that industry to sell their products on your site. You take a percentage of their profits when items sell.
As long as there is still the written word, there will always be editors. Freelance editing and proofreading not only pays a decent hourly wage, it also gives you the chance to read about potentially interesting topics too. What's more, pursuing freelance writing & editing as a business idea can afford you a lifestyle that lets you travel the world as a digital nomad. You can find lots of job postings from companies and individuals in need of writing, proofreading, and editing services on Upwork, which makes this a high-demand opportunity to make money online.
Medium is an online community where anyone can post articles and essays and get them in front of their audience of millions of monthly readers. While it can be a great place to build your audience for your own blog or find customers for your consulting business, with Medium’s new Partner Program, you can now make money online whenever someone reads your articles. Register for free and you can choose whether your articles are freely available or only readable by those people paying $5/month for a premium Medium membership. You’ll make money based on the amount of people who read and engage with your posts each month.