If HackerNew wanted to become more like FarmVille (not that it should), the system could:

* give you karma just for stopping by each day

* give you karma for upvoting other's posts

* give you profiles you could customize by trading in karma

* show you what your friends were upvoting and their Karma

* show you how close you were to attaining moderator status

* allow you to give one virtual gift per day to your favorite contributors

* have your karma decline if you don't stop by in a week