[woollyhat]

I think it would be interesting if users could spend their karma on performing moderator actions, perhaps with some sort of algorithmic exchange rate that converts acquired karma into modcoins.

For example, it might cost 1000 modcoins to pin an article to the top of the page for ten minutes. Or perhaps more of a bold change: 2000 modcoins to make the text of your comment glow with a golden hue to make it more noticeable. 5000 modcoins to display an image of Paul Graham at the top of the thread, smiling beatifically at all the comments below Him. And so on.

This would of course be of no interest to users such as myself who habitually generate throwaway accounts and discard them, but I would be curious to see how high karma users would use such a feature.

[jwarden]

Yeah we have thought of a model where Karma is a measure of how much "marginal value" you have created for other users by your submissions. If we take upvotes as a proxy for value, we can calculate how many additional site-wide upvotes were generated as a result of you submitting your high-upvote-rate story: the number of upvotes your story received minus the number of upvotes the stories that were displace by your story being ranked above them would have received.

Then, we could allow you to spend a part of that value. That is, you can promote a story with a lower upvote rate, thereby decreasing site-wide upvotes by displacing stories with higher upvote rates. You would only be able to spend some fraction of the value you created, so that after you have spent all your Karma, the net value you have created for other users would still be positive.

[mtlmtlmtlmtl]

Interesting idea, but this reminds me too much of Tinder.