If you have a knack for teaching and if you are an expert in some subject, you can become a tutor online for students. There are tons of websites like TutorVista or Tutor.com where you can try out this. You would need a great internet connectivity for this. It can work best for someone who is ready to work late in nights as many students from US and Canada would be right fit for you then.
Domain names cannot be replicated. If one is taken, the only recourse would be to approach the owner to discuss a sale. While there are other variations you could choose, sometimes owning a certain domain (especially if it is attached to your business) can be worth the premium. Often, people will scout out domain names that are still available, buy them, and then sit on them in order to sell them down the road. Depending on who may want the domain down the road, you could sell it for a large markup.
Multiple streams of Income covers this strategy. I highly recomend you read it if for that reason alone. Beats the typcial buy and hold (or is that buy and hope), dollar cost averaging and other so called sensible stategies which don't work unless you have a 20-30 year time horizon. Ask anyone who saw their investments plumet during the Jimmy Carter years back in the 70's how long they had to wait to get their investments back up to break even level. Want to take a guess? Would you believe 15 years? That is close.

We have decided to invest in 2 ETFs, a multi asset allocation ETF (Fixed Inc, alts and div paying equities) and a preferred stock ETF. This will cover almost 45 percent of our deficit. We will be extremely diversified, can access the markets at a very low cost and the investments are liquid. On this pool of $, we have no plans to invade principal unless the investment grows by 20 percent, which we think is unlikely given the characteristics of the investments.
For a person working for a wage, their source of income is their job, or their labor (aka their time that they sell to someone). But you can own a house, and rent it out, and when your renters pay you renter every month, the source of that income check is your rental property, or your house. It would just be called rental income. If you have money in the bank in an account that pays interest, those interest payments are another source of income. We can say the source is interest payments, or we can identify the asset that is generating rent, and say your money in the bank that is generating “rent” (aka interest) is your source of income.