Great list! I’ve used Poshmark to sell clothes/accessories. You take up to 4 photos, add a description, and set a size, color, and brand. I’ve sold 3 items so far (two dresses and a pair of shoes) and it’s easy. The buyer can purchase at listing price or make you an offer, to which you can counter-offer. At all times, you can see what your profit will be from your listed price. Once the transaction is accepted, you are emailed a prepaid shipping label to print. You package your item up in a brown box and ship, and when the seller receives it your funds are released. You can cash out as a direct deposit to a bank account at any time or use the funds to shop. I’ve also purchased a pair of jeans on the site and they arrived as expected. For like-new and designer labels it’s a great way to clear your closet and make a little cash all at once.
So many people dream of writing a book, but never go through with it. Yet no matter what, I’m sure you have experience and value you could give through writing a book. By packaging your skills and knowledge into a downloadable eBook that helps people learn a skill, advance their careers, or start a businesses, you can change someone’s life and even make good money online.
Robo-advisors are diversified investment accounts that are automatically managed by a computer algorithm (as opposed to a human money manager). If you want to invest, but don’t have the money, or don’t want to invest with a money manager, robo-advisors are for you! Robo-advisors make investing easier—and cheaper—so they’re perfect for new investors.
Bookscouter will give you Amazon.com's trade in value, where you mail Amazon the book and get a gift card, they will not give you the used selling price because it's hard to compare apples to oranges. You may be able to get more for your book by selling it as a used book on Amazon, so be sure to double check that price. As an example, the trade in value of a book I looked up was $7.87 but used copies were on sale for $19.87.

Cash Crate is possibly the most popular survey site in the world. The strength of this program is that they are open to residents of all countries. They consistently pay out fast every month. Especially great for people from the USA, Canada, United Kingdom, Australia, India, South Africa, and even other countries that most other survey sites don't allow. They also have games where you can win points and exchange them for great prizes. You also get $1 dollar for free when you join!
Cafe Press: This website allows you to create digital designs that can then be sold on the platform. You'll earn a commission for everything that sells and you'll never have to deal with printing, warehousing, customer service and so on. The site has over 2 million independent designers that have created products being sold online here. If you have some graphic design skills, then this is a great potential source for your web-based income. 
If you have a fondness and talent for taking pictures you can make extra money online by becoming a stock photographer and selling your images to a stock photo company like ShutterStock or iStockPhoto. You’ll get royalties every time someone licenses an image you’ve submitted. To really be successful, build your own photography website to be able to showcase your portfolio and start getting higher-paid private corporate work.
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