If you have a spare bedroom, you can find a roommate or list the space on AirBnB for travelers. Having a roommate is the more passive of the two, as being an Airbnb host will require more work in the form of turning over the room between stays. This is a super painless way to earn $500 to $1,000 a month without much effort – you may even be able to cover your mortgage payment with this extra income!
I would throw in some caution here: if your spouse works at the same company, or in the same industry as you, you are not diversified, and should something happen, you could be in a world of hurt.  Companies do go out of business, companies do lay employees off.  There is nothing wrong with working together, but realize that you are not diversified and you should be trying to maximize other income streams as a result.

I live in NYC where I never thought buying rental property would be possible, but am looking into buying rental property in the Midwest where it cash flows and have someone manage it for me (turnkey real estate investing I guess some would call it). I agree with what Mike said about leverage and tax advantages, but I’m still a newbie to real estate investing so I can’t so how it will go. I have a very small amount in P2P…I’m at around 6.3% It’s okay but I don’t know how liquid it is and it still is relatively new…I’d prefer investing in the stock market.
But, you don't need to go further than that. You can simply write it and publish it and collect the income. That's all. Send out a couple emails to your list (if you have one) or post it on social media, and there you have it. Passive income. Now, the amount of income you receive depends on the quality of the book you've written. How well did you craft the message? How targeted was the information to your audience? It counts.
Building a smartphone or tablet app requires a fair amount of technical expertise, but it can pay off handsomely if successful. It doesn't have to be particularly complex or chock-full of features either; a simple one that solves a problem or is entertaining enough to attract users works fine. You never know what may suddenly become popular. For example, the minimalist game Flappy Bird was such a craze that at one point its developer was earning $50,000 dollars a day through in-app advertising. Of course, expecting a success like that is foolhardy, but one can always hope.
Building a website still remains a viable way of earning passive income online despite it being such a competitive venture. Since the internet is saturated with blogs, an entertaining website featuring quizzes or games is a good alternate. Such websites are not too difficult to make and they are easy to promote on social media. They can attract visitors, who will spend a significant amount of time on the site, in droves. Once a site starts recording several thousand visits each day, use the Google AdSense system to start earning revenue through advertising while you relax.
The goal of creating multiple income streams should be to maximize your potential in each category available to you.  If you are just starting out, it really isn’t reasonable to expect you to generate tons of rental income.  However, if you start maximizing your income generating potential through your primary salary, you will find yourself having excess income that you can reinvest to generate additional income streams and earn more money.
Has this thought ever struck you mind as what if your boss fired you overnight, what your course of action would be? I guess the answer is NOTHING! You have no monthly pay checks coming in, how are you going to put roof above your family’s head? How are you going to manage the bills payment? What would you feed to your family? An answer to all this lies in darkness…complete darkness in that situation. But I have answer to this question, because I am my own boss managing multiple things and earning from all of them at a time, losing one would not be that big deal to me.
The combination of protectionist, import-substitution, Fabian socialism, and social democratic-inspired policies governed India for sometime after the end of British rule. The economy was then characterised by extensive regulation, protectionism, public ownership of large monopolies, pervasive corruption and slow growth.[55][56][57] Since 1991, continuing economic liberalisation has moved the country towards a market-based economy.[55][56] By 2008, India had established itself as one of the world's faster-growing economies.

A good portion of my stock allocation is in growth stocks and structured notes that pay no dividends. The dividend income that comes from stocks is primarily from S&P 500 index exchange-traded funds. Although this is a passive-income report, as I'm still relatively young I'm more interested in building a large financial nut through principal appreciation rather than through dividend investing. As an entrepreneur, I can't help but have a growth mindset.
"Full income" refers to the accumulation of both the monetary and the non-monetary consumption-ability of any given entity, such as a person or a household. According to what the economist Nicholas Barr describes as the "classical definition of income" (the 1938 Haig-Simons definition): "income may be defined as the... sum of (1) the market value of rights exercised in consumption and (2) the change in the value of the store of property rights..." Since the consumption potential of non-monetary goods, such as leisure, cannot be measured, monetary income may be thought of as a proxy for full income.[3] As such, however, it is criticized[by whom?] for being unreliable, i.e. failing to accurately reflect affluence (and thus the consumption opportunities) of any given agent. It omits the utility a person may derive from non-monetary income and, on a macroeconomic level, fails to accurately chart social welfare. According to Barr, "in practice money income as a proportion of total income varies widely and unsystematically. Non-observability of full-income prevent a complete characterization of the individual opportunity set, forcing us to use the unreliable yardstick of money income.
The craziest part of this was I’d wake up in the morning and there would be more money in my bank account, from people who had bought my book overnight. When you think about it, an online store that sells something that’s digital is something that’s open 24 hours a day, 7 days a week, 365 days a year. Using tools, software and systems, you can automate the delivery process so you literally don’t have to do anything to serve that audience. That’s super powerful.

But when so many turn down leasing one and one-half acre for one Wind Turbine for each 80 acres, that lease certainly does not materially affect the rest of the Farm or Ranch grazing pasture and the lease pays much more than the farm crow or grazing pasture lease, just because some lawyer said the lease was too long: 30 years plus 30 year option = 60 years, and the wind turbine company has selling production/electricity contracts for the next 150 years – which is needed to obtain financing!

Thirst for income is likely to continue with interest rates expected to stay low, keeping government bond yields low for longer and their valuations unattractive.  Looking past bonds, the prices of high-dividend shares are historically high, which limits the likelihood that their dividends will rise markedly from here.  Striving too high for an income target tends to push your portfolio further out on the risk spectrum.