These are all great ideas. The problem, which I haven’t heard anyone address, is that all these places want to see a portfolio of your work. If you’re just starting out, it’s not likely you have one. In my case, I did extensive technical and creative writing for my previous company but it was all considered intellectual property for them, thereby preventing me from including it in any personal portfolio of mine. How does one build a portfolio if you already need one to get started?
These little jobs are done by people who log on to a company’s site and choose tasks, which could be as simple as clicking a link. Amazon's Mechanical Turk is one of the most well-known sites of this type. Also, there are crowdsourcing projects, which are similar to data entry, where companies engage an army of virtual workers to each do one small part of a larger project.