Post Ranking?

Hello everybody,

I am looking for a addnon feature for PunBB and fail to see whether someone else already came up with this - please don't bite me if i should have seen it somewhere around.

What i am looking for is a modification that enables users (a sertain user group, at best) to rank posts similar to what Amazon does with recensions (0 points for a horrible entry, 10 points for a very good one)

Is there something like this out there?

Thanks for your help!