If you're serious about making money online, start a blog. Blogging is one of the easiest and most sustainable income sources. As long as the blog is setup the right way, in the right niche, with the right content targeted at the right audience, and the offer is complementary to the content, you could make a tremendous amount of passive income from a blog.
Mechanical Turk is Amazon's take on micro-jobs. These are small miniscule-jobs that you can do for other people, which they call HITs, or Human Intelligence Tasks. These are super simple tasks that anyone can do. Some examples are listing off some URLs with certain kinds of images for one cent, or recording a few phrases with a microphone for 6 cents.
Robert said he did an average of 4-6 of these gigs per year for a while depending on his schedule and the work involved. The best part is, he charged a flat rate that usually worked out to around $100 per hour. And remember, this was pay he was earning to advise people on the best ways to use social media tools like Facebook and Pinterest to grow their brands.