For example, you can design digital products, like animal clipart or a downloadable wedding poem that could be printed by the customer. Your design could be resold thousands of times without needing to create each item or ship it. Once you create your digital product and list it on a site like Etsy or Ebay, the revenue flows in with little oversight.
This can be a little easier said than done, but if you have a large social media following, you can definitely earn money promoting a product or advertising for a company. You can even combine this with different marketing campaigns if you are an influencer and have your own blog (advertisement + affiliate income). This is how many bloggers make money! Again, it is not 100% passive but once set up correctly and then scaled, can be surprisingly lucrative.
When money is lent to a partnership or S-corporation acting as a pass-through entity (essentially a business that is designed to reduce the effects of double taxation) by that entity’s owner, the interest income on that loan to the portfolio income can qualify as passive income. As the IRS language reads: "Certain self-charged interest income or deductions may be treated as passive activity gross income or passive activity deductions if the loan proceeds are used in a passive activity."
In equity valuation, residual income represents an economic earnings stream and valuation method for estimating the intrinsic value of a company's common stock. The residual income valuation model values a company as the sum of book value and the present value of expected future residual income. Residual income attempts to measure economic profit, which is the profit remaining after the deduction of opportunity costs for all sources of capital.