Perhaps there is a right to a return on investment basis. And one that potentially very scalable.
Consider MTurk workers. What they all have in common? Tens of thousands of people - each of them are interested to make money online.
Of course it is difficult to do much in MTurk. So what is the next logical step for a Turker? Fiverr.
And I just see so happen to offer a course of Fiverr for sale.
So how about the design of a task, the work to promote the course for them? Perhaps you might have to read the sales page and a survey.
Start with questions that get them to express positive feelings about the product: "What was the most attractive part" Then the issues that are to be displayed with the product are: "When describing the system, how much money do you think were implemented ? "and so on, resulting in the first month to a kind of soft closing. That would be a little secret, of course.
You can meet the requirements of the task, adjust your target audience.
And maybe some of them to buy. Only one way to find out. -)
PS If you decide to try, I think probably increase the acceptance of Bitcoin your conversions significantly. It is popular among people Turker.