Our project has a points system, users are rewarded for useful actions:
5 points per comment
30 points for adding a case study / post
250 points for each registered user on your affiliate link (see the bottom of the page)
* For the cheat points, the user can get a ban his account.
What can I spend points on:
Set a case study at the top of the category for 1000 points
Set a case study at the top of the category for a week 5000 points
Place a banner at the top of the main page for a day of 5000 points
Verify case 5000 points
Personal hour consultation with the creator of the project 30,000 points