[SD] Passive income strategies

[RBP]

[SD] Serious discussion tagged, please stay on topic.

I have been exploring ideas for passive income. Specifically, for me anyway, zero investment passive income. Building income, and hopefully wealth, through multiple streams.

What is passive income? Generally, it's a place you put some initial time and/or investment, then allow the income to flow back with limited or no active involvement. Most strategies are investment strategies, which don't work if you don't have free capital. Things like managed properties or stock investments. The trick is to devise multiple streams that (hopefully) provide some return over time. If they do, it's found money.

As some of you know I have one I have been creating and selling digital art online. One is fairly passive, RedBubble. You upload photos or artwork, do some social media work and get your family and friends to do some, then hopefully you have a few items that take off. From reading about T-shirt designers, they have a lot of duds, but when one hits it pays off royally. My other is Etsy, which is more active since it includes custom projects, but the time investment is minimal.

My other current strategy is idea licensing. The concept is that you can get provisional patents, or sometimes no patent at all, and license ideas to manufacturing companies. External idea licensing has become mainstream, and while it may not be super easy, one idea can pay large dividends. In many cases, as a consumer, you already know what improvements to existing products could be made. And many companies will pay you a royalty on sales for introducing that idea.

I have started reading more from an author named Stephen Key. His books are titled "One Simple Idea" and "Selling your ideas with or without a patent". I have 2 ideas in the hopper and will be working on more as I read through the business process to make it happen.

Is anyone using any passive income strategies? If so, what have you learned? Have any good resources for exploring passive income?