It's a point based system, to which users can gain points for voting for powerscape on different top lists, each time they vote they gain an amount of points of which then count towards being able to buy donatorship or items at a discounted price
Maybe 10 Points = 5% discount (etc, etc)
This would mean that when you vote on different sites you get points - different sites gives you a different amount of points - this would allow us to focus on one top site more than another because people are more likely to vote on the site that gives them more points.
I don't know if you could implement something like this or whether it's too complex?