Mechanical Turk: Amazon's Mechanical Turk is a resource for doing human-intelligence tasks, or as the site commonly refers to them, HITs. You get paid a very small fee for any given HIT and you'll need a good deal of volume to make a substantial amount of money. But it is a resource you can use in your spare time to generate a small income online. 
Great list! I have another to consider that I personally have 35+ years experience providing. Clean up litter outside commercial properties on foot using inexpensive hand tools. It’s almost as easy to do as going for a walk! I started doing this as a side gig in 1981 and soon grew it into a profitable full-time business. I share my experience in my book, Cleanlots.
Yes, companies will pay you to install apps (or place ads) on your cell phone and leave them there. These apps often run in the background and track your spending/purchasing habits but if you’re not one to really care who knows what groceries you’re buying that week then this is seriously the easiest way to make upwards of $300 per year for no reason.
12. Bubblews (parental consent needed)-Get paid for your thoughts, opinions, experiences through social media. Receive compensation from advertisement revenue-share based on the number of likes, comments, and views your post receives. You can redeem to your PayPal once your account has reached $50. This site reminds me of Tumblr with the built in network of users and tags that you can search for and follow.
It will probably take a couple years to build a sustainable, passive income. That is the 1st car I have EVER purchased myself at age 29 (I was broke until then and leased from my parents). But the time committed to affiliate marketing and creating great tutorials and YouTube videos was worth it… I work for myself, there is virtually no limit on how much I can make, my schedule is flexible, and I collect enough passive income to live how I want.

It would be a definite mistake to promote everything by registering with different affiliate programs. You can’t focus on each of them deeply and the result would be a disappointment. Instead of promoting everything, just promote a few products which are unique, profitable or can reach large masses. So, you need to understand market needs and desires and place your products accordingly.

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