I had posted in the Gameplay Advice column, asking for feedback on card mechanic where you reward players with a Meta-Wealth asset card, to reward them for posts that are extraordinary contributions to the story.

Several RPG systems have a way of challenging the players this way - Exalted potentially rewards players with experience and more dice vs. a roll for example.

For Storium, the player can later use that card during a post to have their character find/purchase/upgrade something amazing for their character.