A few people who started their own YouTube channel when the video-sharing site was in its nascent stage are now millionaires. Now that YouTube has become immensely popular with hordes of people running their own channels, making a million dollars is considerably more difficult, but earning a respectable sum of money is still possible. As always, you'll need to find a niche that isn't yet saturated and focus on making engaging videos around it. Once you start raking up views and subscriptions, the money will start flowing in with minimum effort on your part.
That's odd, because lot of these questions are actually pretty easy to answer. The IRS is good about publishing the data. Given that – and given the recent interest in personal income inequality, I decided to write a little bit about the different kinds of income people report on their tax returns. A longer paper – Sources of Personal Income – is here, but for a brief overview, you might want to check out the top ten sources of income:

There are many success stories you’ll run into of what it takes to generate multiple streams of income. However, one of the most important tips is to take on multiple clients. One client being your income source is bad news. They could voluntarily or involuntarily leave you high and dry. For instance, their business may begin to suffer and they no longer have the funds to pay you. Well, that is your income stream; gone without warning.

I run several online businesses now (all it takes to start one is a domain, hosting, and maybe incorporation). There are two notable ones. The first is meal plan membership site called $5 Meal Plan that I co-founded with Erin Chase of $5 Dinners. The second is the umbrella of blogs I run, including this one and Scotch Addict. They pay me ordinary income as well as qualified distributions since I'm a partner.
"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.
You can find dividend stocks using Google Finance Stock Screener which is free to use. Set the search criteria for the P/E Ratio, and Dividend yield (shown as a percentage) criteria. You can set minimum and maximum values; in the dividend yield box, set it between 2 and 100. This will search for stocks that pay dividends worth between 2-100% of the current stock price.
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.
However, under certain circumstances, payment for personal services performed in the United States is not considered income from sources within the United States. For example, personal services performed by an independent nonresident alien contractor specifically exempted by a tax treaty. For more examples, see the Pay for Personal Service section in Publication 515, Withholding of Tax on Nonresident Aliens and Foreign Entities.
This is the best post I’ve seen on passive income streams. I’m similar to you in that I worked in IBanking for a few years but wanted out. My approach is a little different, instead of starting with the CD’s, I’m trying to build up my net worth with riskier asset classes such as stocks and real estate to get the benefit of compounding. Then, as I approach my retirement year goal, I’ll start moving them into CD and bond ladders. In theory at least, it’s best to have the highest net worth just before retirement, then convert them to risk free passive income. You’re method is more patient and probably more practical than mine. I guess I’m willing to take more risks.
* I use Personal Capital to track all my finances in one place. It’s much easier to use their free software to follow 28 accounts on one platform than to log into various accounts to check my balances. They’ve also got great tools for x-raying your portfolio for excessive fees, recommending a more optimized asset allocation, and planning for retirement with their Retirement Planner.
Investment in real estate can also be a source of a second income. If you have a decent sum of money lying around, you can use it to invest it to buy your second home. You may even take a home loan to finance your second home. This can become a source of income for you when you rent it to someone. These monthly rents would become your secondary monthly income. The key to making more money with rental properties lies in buying smart. Not all kind of property is going to give you a good return. Hence, analyzing the potential real estate opportunities is very important. The monthly rent highly depends on the area/location of the property hence it is highly important that you select the location of your property very wisely, keeping in mind the rent factor. You can save much even after your home loan EMIs. In addition to this, you can also avail tax exemption on the purchase of your property if it is through a home loan.
* Freelance writing: Quality freelance writing takes tremendous effort. Ironically, the better the quality of your writing, the more you don’t want to freelance and just keep the articles for your own site. Freelancing is a great way to earn side income, however, it’s not really for me. I’ll probably take on one or two freelance jobs maximum per year and write no more than four articles a month elsewhere.
Last but not least Blogging, which is close to my heart. It require lot of patience, skills, knowledge and flair for writing to be a successful blogger. Besides basic skills, you need expertise in SEO & SEM to drive traffic on your blog. For successful bloggers, Blogging is full time income source. Though this place is full of copycats but trust me originality pays. Bloggers earn from content writing, affiliate programs, advertisement and through public appearance/consultancy. Organizations have realized the importance of social media impact and blogs are considered to be the best way to drive traffic on website & customer engagement. Infact many organizations have started hiring full time bloggers.

And, let’s face it; not everyone wants to sling body wraps or nutrition shakes to their family and friends. That’s why offering a service is often one of the best, and least uncomfortable, ways to earn side income doing something you love. Maybe you want to clean houses or rake leaves or help people file their taxes. It’s totally up to you, and that’s the beauty of this option.