Considering that you have a finite amount of time, passive income should make up a large part of your work. And if you're serious about generating any semblance of income online, then passive income should be one of your sole goals and ambitions. Why? Simply this. Wouldn't you prefer to do the work one time and get paid repeatedly as opposed to relying on your time to generate that income?
No matter what method you select for generating your online income, there's one very important thing to understand. Today, across this globe, with its 7+ billion inhabitants, there are two recurring things that people are looking for more of. Either people want more time or they want more money. The truth? Time is far more valuable than money. You can't recreate time. Once it's spent, it's gone forever. Not money.
Donating plasma can actually work out better than selling your blood. It takes longer to donate plasma because they will put your red blood cells back in your system. The upside is that you can donate plasma as much as twice a week and you can make anywhere from $40-$60 per donation. You can make that $100 in less than a week if you can stomach the needle.
Great article, I have tried a few over the years. I had a side business cleaning offices for years. It did great, but I hated never being able to take more than 3-4 days vacation, so I eventually gave up. I tried MTurk, but if you multiplied my earnings on an hourly basis, it was a little over $6/hr. My blog is much worse, probably less than $0.25/hr.