There is a potentially unlimited number of ways we can implement the above models, and our options are really only limited our imagination. The main point to keep in mind is that we need to provide a certain level of value to people, enough value to make it worth paying for. This value could be a real, measurable value, such as in the case of a physical product or a perceived, emotional value such as higher status in a social network.
There are some common methods of implementation though that are worth looking at. Both of these are very compatible with a free economy, as the primary product is mostly provided for free.
A freemium is where a portion of a service or part of an information product is given away for free to entice people to try it out, and then once they are interested in the service/product they are up sold to the complete service.
This is a very common method in use by many web services today because of its effectiveness. A higher percentage...