The downside with this model is that you are still trading hours for dollars, which is a violation of my holy trinity concept. It’s not necessarily the worst option – and many people enjoy the life of a high-paid consultant very much – but it does have the inherent limitation that a service is not replicable unless you personally do it yourself or hire people to do it for you, both activities that take time and/or resources.
If you’re a website or blog owner, you can sell a portion of your page space to advertisers and earn money passively each time the ads are clicked on by your target audience or visitors to your website. While the actual placing of the ads is completely free, the earning capacity of cost-per-click (CPC) advertising is based on the level of traffic to your site and the cost per click and click-through rate, or CTR. The most popular way to earn money today through advertising clicks is through Google AdSense or similar advertisers. Other ways of effective online advertising include RSS feeds and direct banners.
Audiobooks are another lucrative form of passive income. Speaking from experience, when done right, audiobooks can easily produce thousands upon thousands of dollars per month on autopilot. However, quality and the delivery of high-value content must be the key aim at all times. Leverage Amazon's ACX platform to publish audiobooks for inclusion in Apple's audiobook store and on Audible.com.
Robo-advisors are diversified investment accounts that are automatically managed by a computer algorithm (as opposed to a human money manager). If you want to invest, but don’t have the money, or don’t want to invest with a money manager, robo-advisors are for you! Robo-advisors make investing easier—and cheaper—so they’re perfect for new investors.