Last week, Alex Tabarrok (who is co-authoring a principles textbook with Tyler Cowen) asked me for good examples of non-monetary incentives. Perhaps the best response is: "Do what I want, and I'll be your friend." Depending upon who makes the offer, moreover, there may be large secondary effects: It's good to be friends with people who have lots of friends themselves.
1. When you register on the discussion boards, you start with a Reputation Power of 0.
2. Anyone who likes a post you write has the option to "Rep" you. This adds approximately 1% of their Reputation score to your Reputation (with no dimunition of theirs). For example, the game's Line Developer has a Rep Power of 4009, so if he Reps you, your Rep jumps up by 40.
This largely a more transparent version of the process that Google uses. The main difference is that on the Hero boards, giving Rep is a conscious decision (with Google, though, you can make a conscious decision not to count a link - see here). You don't get credit just because people are talking about you.
3. The catch: You have to write at least 50 posts in order to get credit for the Rep you've earned.
I just crossed the 50 post threshhold after two years of irregular posting. Suddenly all of my censored Reputation kicked in, so I leaped from 0 to 55. Now I too can bestow Reputation on others, though 1% of 55 isn't much... And yet, I'd be lying if I didn't admit that this was a motivation to post!
Well, at least it makes more sense than worrying what the people you knew in high school think about you.