There are a couple of problems with direct investment in real estate though. It’s expensive to buy even a single property, a minimum of tens of thousands of dollars, and there’s no way most investors can build a portfolio of different property types and in different regions to protect from those risks when you have all your money in just one or two investments.
Stocks (shares) paying dividends are typically a reliable source of income but they have higher risk of capital losses than cash and bonds. So, it’s wise not to chase yield indiscriminately.  The 10 highest yielding stocks on the ASX 200 (the 200 largest companies in Australia) are shown in the table below.  But their share price performance on average over the last year has been underwhelming, as shown in the far right column:
India has one of the fastest growing service sectors in the world with an annual growth rate above 9% since 2001, which contributed to 57% of GDP in 2012–13.[42] India has become a major exporter of IT services, Business Process Outsourcing (BPO) services, and software services with $154 billion revenue in FY 2017.[43][42] This is the fastest-growing part of the economy.[44] The IT industry continues to be the largest private-sector employer in India.[45][46] India is the third-largest start-up hub in the world with over 3,100 technology start-ups in 2014–15.[47] The agricultural sector is the largest employer in India's economy but contributes to a declining share of its GDP (17% in 2013–14). India ranks second worldwide in farm output.[48] The industry (manufacturing) sector has held a steady share of its economic contribution (26% of GDP in 2013–14).[49] The Indian automobile industry is one of the largest in the world with an annual production of 21.48 million vehicles (mostly two and three-wheelers) in 2013–14.[50] India had $600 billion worth of retail market in 2015 and one of world's fastest growing e-commerce markets.[51][52]
​I’ve been into home décor lately and I had to turn to Etsy to find exactly what I wanted. I ended up purchasing digital files of the artwork I wanted printed out! The seller had made a bunch of wall art, digitized, and listed it on Etsy for instant download. There are other popular digital files on Etsy as well such as monthly planners. If you’re into graphic design this could be an amazing passive income idea for you.
Example. Jean Blanc, a citizen and resident of Canada, is employed as a professional hockey player by a U.S. hockey club. Under Jean's contract, he received $150,000 for 242 days of play during the year. This includes days spent at pre-season training camp, days during the regular season, and playoff game days. Of the 242 days, 194 days were spent performing services in the United States and 48 days performing services in Canada. The amount of U.S. source income is $120,248 ((194 ÷ 242) × $150,000).
It’s a (mostly) short term, higher risk, higher reward place to invest cash that has a low correlation with the stock market, but is far more passive than buying and managing properties, has more opportunity for diversification than private placements (minimums of 5-10K, rather than 100K), and most of the equity offerings (and all of the debt offerings) provide monthly or quarterly incomes. Unlike a REIT, you can choose exactly which projects you wish to invest in.
While compiling this list, I did my best to avoid scams, and stick with practical ideas that work. I have tried many (but not all) of these ideas. Some of these helped me earned a few dollars here and there, but there are some that helped me earn extra money on the side every single day — and some are still providing me with revenue! Note that not all ideas will fit your skills and abilities. What works for you depends on your abilities and your current financial situation.

However, I think for those who are willing to do what it takes, the sky is the absolute limit. As an example, I’m trying to take a page out of FinancialSamauri’s book and create an online personal finance and investing blog. It is an enormous undertaking, and as a new blogger, there is a seemingly endless amount of work to be done. That said, I hope that one day I can not only generate some passive income from the hours of work I have put and will put into the project, but I hope to be able to help OTHERS reach their financial goals.

Thanks for writing this Mr. Samurai. I just got over the student loan hump but I feel pretty good about it at 27 having a graduate degree and being 100% debt free. Now that I’m on the other side it is good for my brain to absorb some of your knowledge regarding passive income investments. I love gleaning wisdom from older folks who have been there and done that. Mentors rock!
Doesn’t it sound awe-inspiring to have more than one income source? You already have one source of work with a steady flow of income and then you are creating more and more work for you with more income for you. Who does not want to have lots of money in their bank accounts floating all around? For the person who values financial security and their ultimate dream is financial freedom, creating more than one source of income becomes a necessity not just desire.
These days, low-risk bond yields aren’t enough to meet most income needs. When investing in bonds, the income typically comes as coupon payments – contractually guaranteed interest payments at predictable intervals.  There are many kinds of bond income available, so you must strike a balance between reaching for higher income (yield) and limiting risk.