Some type of karma system would be interesting. Ex: Post a submission, get high ratings, you would gain good karma. But if you got lower ratings you would gain bad karma. Possibly have a +1 or -1 karma button on a profile. Karma wouldn't be tradable. Getting a post EFified would gain good karma. Admins/Moderators could give you good/bad karma depending on what you have done.
Please note that I am just throwing out ideas, and I will organize it later.