Ebooks are one of my favorite sources of passive income. Now, you can do this the simple way and just publish it on Amazon's KDP. Or, you can go all out and build yourself a book funnel. Book funnels are powerful, but they won't be fully passive. For example, if you do a free-plus-shipping offer for your ebook (converting it into a physical book), you'll need to create some one-time offers (i.e. extra training) and up-sells (i.e. an audiobook). But, a book funnel can be very powerful.
What I’m doing: I use this site to write out goals like 1) Generating $200,000 a year working 4 hours a day or less, 2) Trying to make winning investments, and 3) Keeping track of my passive income streams with free financial tools. My site and the community helps keep me accountable for progress. It’s important I do what I say, otherwise, what the hell is the point? You should consider starting a site or at least a private journal. Write out your specific goals, tell several close friends and stick to the plan.
On-demand: More than a decade after “The Blair Witch Project” and its viral-before-viral-was-a-thing campaign, the producers of “Paranormal Activity,” who made their 2007 film for about $15,000, invited those interested in the film to demand their local theaters show the movie. The result? A wide, nationwide release and more than $107 million in box office revenue in the U.S. alone. (2, 3)
For example, you might take photos and have them available for a fee at sites such as shutterstock.com or istockphoto.com. Similarly, you can create and upload designs at sites such as zazzle.com and cafepress.com, where people can buy them imprinted on shirts, mugs, and so on. Similarly, if you write an e-book (which can be as short as 6,000 or so words), you might find that people are interested in buying it, perhaps via Amazon.com's direct publishing service.
3. Start as soon as possible. Building a livable passive-income stream takes a tremendously long time, largely because of declining interest rates since the late 1980s. Gone are the days of making a 5%-plus return on a short-term CD or savings account. Today, the best 12-month CD is at 2.5%, and the best money-market rate is about 1.85%, which is not bad, considering such rates were below 0.5% just a couple of years ago. Know that every $100 you save can generate at least $2.5 in passive income.
I've now only got an SF rental condo and a Lake Tahoe vacation rental in my real-estate-rental portfolio. Although I miss my old house, I certainly don't miss paying $23,000 a year in property taxes and another mortgage, and dealing with leaks and managing terrible tenants. I drove by the other day and couldn't believe how much noisier and busier the street was than where I currently live. I wouldn't be comfortable raising my son there.
What if there was a way for you to effectively make money while you sleep? Sounds like a dream come true, right? Even for the biggest workaholics, there are only so many hours in a day. If only you could get paid multiple times for something you did once—that’s exactly how passive income works! Thanks to technology, the potential to create multiple income streams is even easier than ever before. We’re no longer held back by the limitations of a traditional 9-to-5 job, and financial freedom is at our fingertips. Even if you already work a full-time job you can still improve your financial health with passive income.
As for me, I started focusing on passive income last year, but have owned rentals for 5 years. $25k now outside retirement accounts in mostly real estate. Looking to invest another $500k cash into real estate to get about $65k, and then 1031 under performers next year to hopefully boost that a bit higher. Heavy in real estate, but feels lower risk than the stock market to me if you have cashflowing properties. Real estate is inflation adjusted, and built in cashflow raise when the loan pays off.
However, when you lack the money, you need time. You'll need to invest the upfront time now in order to reap the benefits of automatic income later. It just doesn't happen overnight. So don't expect it to. However, you can do this without quitting your day job. All it takes is some sincere effort over a consistent period, and voila! But, to get there, you'll need to consistently burn the midnight oil or get up at the crack of dawn. Your choice.
Many content creators, or people who simply upload a random video, have found themselves become famous almost overnight. It’s not about the resources and budget — it’s all about what catches the attention of the internet. Marketers don’t always need a large-scale production with a celebrity to make their campaign funny, surprising, relatable, or informational. 

The introduction of social media has caused a change how viral marketing is used and the speed at which information is spread and users interact.[35] This has prompted many companies to use social media as a way to market themselves and their products, with Elsamari Botha and Mignon Reyneke stating that viral messages are "playing an increasingly important role in influencing and shifting public opinion on corporate reputations, brands, and products as well as political parties and public personalities to name but a few."[35]
Apple maintains it’s viral appeal, with the iPhone X through their launch of the "Selfies on iPhone X" campaign. The secret to this example of viral marketing (which has clocked up over millions views both online and offline) is very simple: a product so great that it turns people into fans of the brand all on its own. People love themselves. If they have the possibility of spreading this love digitally through selfies, it’s almost a guaranteed win. The iPhone X’s brilliant selfie feature spread virally through various media forms before apple repurposed the viral content into one masterpiece, the iPhone X selfies film. As one of the YouTube comments says, “It’s the most beautiful thing I’ve ever seen”… This viral marketing through video has allowed Apple to spread key features such as their Portrait Lighting effects and their TrueDepth camera.