Make contribution like a free market. The more you pay (with some kind of credit), the more visibility your post/comment will get. If people like your contribut

Make contribution like a free market. The more you pay (with some kind of credit), the more visibility your post/comment will get. If people like your contributions, you earn credits. If they don't, you lose them. I'm sure the gambling aspect (big gains if you invest a lot and wisely) would hook a ton of people. Quality, hopefully, would follow.