You can sell your ebooks through Amazon's Kindle program or Apple's iTunes Connect, which gives you access to a large majority of the digital-book reading market and the barriers for entry are incredibly low. You don't need to invest lots of money to make this happen, but you do need to invest lots of time, not only in writing the ebooks, but in marketing them as well.
Amazon will have you work on micro-projects that require some sort of human interaction. Tasks can include translating a paragraph into English (or another language), rating the search results for certain keywords, or reworking an article. The tasks are simple, and you will be paid a small amount to complete each. But if you do enough tasks quickly, you can make a respectable amount of money.
If you have a good idea for an app, and the skills to create it, then producing your own premium app can be profitable. However, with so many free apps available, it may be hard to convince people to pay. If you want to go down the premium app route, consider having a basic free version to encourage people to download the app in the first place. You can then provide the option of upgrading to a premium plan once users realize how useful the app is.
The money is most certainly in the list. If you're at all interested in online marketing, setup email software and create a lead magnet that you can use in your sales funnel. Then, build up that list. It's often said that you can expect to earn about $1 per subscriber per month. If you have a list of 10,000 subscribers, that means you can earn roughly around $10,000 per month. You will need to deliver value and not pitch them on every email, but it is a very achievable goal in a short period.
Running a coupons website can be very lucrative. Find a coupon niche, select a WordPress coupon theme, and then display relevant coupons on your site. When your audience uses the coupon codes or discount links, you will earn an affiliate cut, for example, you could set-up a site dedicated to iHerb Coupons or add a page to your website with Web Hosting Promo Codes. Coupon websites are quite high maintenance as they need to be constantly updated with new offers. However, if you build up an engaged audience and allow them to post coupons and discounts they have found themselves, then quite quickly your workload will reduce.
The peer-to-peer concept is coming to virtually every corner of human existence. That includes the hospitality industry. Through AirBnB you can actually rent out your house for various lengths of time for a predetermined fee. That gives you an extra income on your house and gives the visitor the benefit of having an entire house, rather than being crammed into a single hotel room.

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.
Fiverr: Israeli-based Fivver was started in 2010 by Shal Wininger and Micha Kaufam. It's a great resource for selling just about any service online. You can offer gigs as low as $5 but also get paid much more for upgrades and add-ons. There are plenty of providers earning 6 figures on Fiverr so it's definitely a worthwhile cause for generating a healthy income. Just ensure that you provide some serious value. 
Running a coupons website can be very lucrative. Find a coupon niche, select a WordPress coupon theme, and then display relevant coupons on your site. When your audience uses the coupon codes or discount links, you will earn an affiliate cut, for example, you could set-up a site dedicated to iHerb Coupons or add a page to your website with Web Hosting Promo Codes. Coupon websites are quite high maintenance as they need to be constantly updated with new offers. However, if you build up an engaged audience and allow them to post coupons and discounts they have found themselves, then quite quickly your workload will reduce.
If you’ve got experience and expertise in a specific area of business, there are hundreds if not thousands of business owners who would love to jump on a phone call and pick your brain. This can be an easy way to make extra money online and to hone your skills to use in your consulting or freelance business. Sites like Clarity.fm let you create a profile where entrepreneurs and business owners can pre-pay to book a phone call with you for a set amount of time. Whether you’re an expert in raising money for startups, building apps, or running a restaurant, you can make extra money selling a few minutes of your time to people in need.
Domain name trading has been around for the last couple decades, and while most slam-dunk names have long been sold off, there’s still plenty of others that you can get your hands on for relatively cheap and broker as a way to make money online. Before you dive in, however, beware that some experts doubt the long-term viability of this idea for making money online. However, there’s always the change you might just land on a lucrative domain name for a future billion-dollar company. To get you started, here are some tips from GoDaddy, arguably the world’s largest and most famous repository of domain names.
Need more ideas on how to make money online? Another strategy is using webinars to market your product, service, or course. I’ve done webinars to promote my financial planning practice and to drum up interest in my online course for financial advisors. With a webinar, you’re basically offering a lot of tips and advice for free — usually in a live format. At the end though, you pitch your paid product or service with the goal of securing a few deals.
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