One great way to generate a passive income is through affiliate marketing. Now, this does depend on the size of your list. Yes, size matters when it comes to your list. Especially if you're looking to make some serious money and do it on autopilot. But, list-building takes time. It doesn't happen overnight. And you need to add value to your list or you become obsolete.
For those of you who don’t want to come up with a $220,000 downpayment and a $900,000 mortgage to buy the median home in SF or NYC, who don’t want to deal with tenants or remodeling, and who wants to not do any work after the investment is made, check out Fundrise. They are my favorite real estate crowdsourcing company founded in 2012 and based in Washington DC. They are pioneers in the eREIT product offering and they’re raising an Opportunity Fund to take advantage of new tax favorable laws.

Secondly – and this is just quibbling – I’d change that risk score. The risk of private equity is incredibly high and should be considerably riskier than bonds! You are providing a typically very large amount of capital to one business that you agree to have no control over, and the success or failure of that business over a locked, predefined term determines your return. And in the few deals I’ve negotiated for clients, my experience has been that there are often management fees, performance fees, etc. that may cut into your potential gains, anyway. You’re putting a lot of eggs in one basket, and promising an omelet or two to the management no matter what. You really need to be confident that you found the next Uber before you take this giant risk!

My returns are based on full cash purchase of the properties, as it is hard to compare the attractiveness of properties at different price ranges when only calculating down payment or properties that need very little rehab/updates. I did think about the scores assigned to each factor, but I believe tax deductions are a SIGNIFICANT factor when comparing passive income steams.
I have not. While I am intrigued with the possibility of making online income, it seems to be less passive then how I want to spend my time. Regarding your blog / site, you have done quite well for yourself. However, you have to keep pumping out content or your site would eventually go out of business. That sounds like more of a commitment then I would want. Regarding your book sales, it is probably relatively passive now, but certainly was not when you were writing the book. Now if you love it, great. Just not for me.
I think that rental real estate is not perfectly passive income. Landlords need to make a lot not only in order to list the property, but also to keep reliable tenants. So, I would say that it could a challenging job, for people, who have rental real estate but not a source of passive income. Maintenance and management costs that should to be also considered.
Real estate has another perk: Tax law in the US (and most countries) has been written by landowners. There are some ridiculous loopholes, like the ability to deduct expenses (and maybe even some interest) as a cost of doing business. Also, you can sell the property and buy another one without paying taxes. I won’t go into detail here, but Real Estate is my favorite form of passive income, and it makes up over 50% of my portfolio. See the next section for a breakdown.
When a taxpayer records a loss on a passive activity, only passive activity profits can have their deductions offset instead of the income as a whole. It would be considered prudent for a person to ensure all the passive activities were classified that way so they can make the most of the tax deduction. These deductions are allocated for the next tax year and are applied in a reasonable manner that takes into account the next year's earnings or losses.