Drive for Uber or Lyft: If you're in a locale where you can find Uber or Lyft (or even one of the many competitors around the world such as China's Didi), you could easily make a respectable income. The hours are flexible and you can work as you see fit, making it perfect even if you currently have full-time employment but are looking to make some money on the side.
Also I would like to add a new one for your paid to post blogging section. Blogvertise has been my favorite place to get offers. If someone wants one done for $5 and you would like $10, you can request that and in most cases, they will accept the offer providing you include 2 links in your post back to them and write at least 300 words. Some require PR1 and higher blogs but to join you don’t have to have any(I have one blog with a PR1 and one with a 0 listed and both get work every month)
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.
Products – You can create your product, like an ebook or software. You would then use your blog site as a promotion tool to obtain people to get your product. As long as you produce a legitimate product having a whole wide range of value, you need to be able to acquire some buyers, but like everything else having a blog, you’ll want the traffic to have the sells.
Find a profitable niche: We’ve talked about this a lot. But, where are you most comfortable. What niche do your skills, values, and interests intersect? Do you have 10 years of experience as a technical writer? Do you have long-standing PR relationships that’ll be invaluable in helping startups launch a successful crowdfunding campaign? Determine what makes your value unique, and lean heavily on showcasing that strength to your potential clients.
Many people fancy themselves as designers. If you have a unique idea for a new product then it may be time to get it designed. This can be a long process involving prototypes, discussions with factories, package design, and much more. However, the profits once the product is on the market could be substantial. And remember, with Amazon FBA, your products can all be stored and shipped by Amazon, giving you time to think up your next invention. Learn more about Amazon FBA with my How To Start An Amazon FBA Business Guide.