6. IZEA – IZEA works in addition to a blog or on its own. You get paid to blog, tweet, take photos and take videos. The pay is mostly based on your following, so if you want to make money with your tweets, you’ll need to grow you Twitter following.  Likewise, if you want to make money with blogs, you’ll need substantial blog traffic (more on blogging below).

If you’re willing to take on some risk and have the heart of a true hustler, you can make extra money online doing commission-only sales for startups and other businesses. While you won’t be getting a regular salary, with the right sales strategies and skills as an inside sales rep, you can make decent money for each sale you bring in. And because you’ll most likely be working with startups, if you can negotiate a little equity you could profit big time if you're pitching a solid product and the startup succeeds.
A blog highlights your technical ability and showcases your ability to write blog posts. Your blog can be about different topics than those you write about for your clients. In fact, it should be on a topic that interests you. Visitors will see that you can not only write, but you can also build an online community. A good blog has the potential to earn you many referrals for more clients.[24]
I had run across my first pre-forclosure deal and needed to get a basic understanding of the steps and processes. Peter and David's book provided that wonderfully. I was able to use the steps and scripts to sign up a deal, provide help to a stressed-out seller and reach the proper department at the lender. The suggestions of how to talk to both the seller and the lender have been very helpful with dealing with the human side of things. I felt very comfortable with the style and the seller has been very appreciative. I didn't feel manipulative at all.
Amazon Mechanical Turk is a service that lets you make money online through doing paid microtasks. Each task is something simple that requires human interaction like rating search results, checking for the right spelling on search terms, categorizing the tone of an article, or even basic translating. You can do these tasks from anywhere you want and make money online from the world’s largest e-retailer.
Etsy: While Etsy's popularity has declined recently, it's still a great resource for selling handmade items online. No need for complex ecommerce sites or merchant accounts or any sort of automation. The company takes a commission of every sale and charges a small listing fee per item. But many still use Etsy as their primary source of income. The best part is that you can also sell digital products on here such as poster designs. 
Multi-vendor marketplaces, like ThemeForest, can be very successful. Chose a niche and create a vendor website for it. Your marketplace could be anything, from a platform for local artists to sell their work on, to an online digital product store. Once set up, invite people in that industry to sell their products on your site. You take a percentage of their profits when items sell.
As I get older (and hopefully wiser), I’ve begun to understand some of the money mistakes I’ve made along the way. After reading Why Smart People Make Big Money Mistakes, I see that I’ve fallen prey to many of the issues raised by this excellent book. This book does a wonderful job of explaining how humans are naturally inclined to focus on the short term and have multiple inherent biases in their reasoning that lead to big money mistakes. More importantly, it provides thoughtful approaches to minimize those mistakes so that the reader will be better able to manage their finances.
This has become a popular business model for online entrepreneurs over the past several years, and will probably just continue to grow in popularity. The best thing about selling online courses is that once you do the up-front work in creating the course and setting up your marketing strategy, you can get paid over and over again for work you do once.