Need plugin suggestion: article / review rating

I need a little suggestion for a plugin which would do pretty much simple thing…

I’ve got blog with reviews. I’d like to be able to put a grade for a review, preferably with some plugin, which would store grades in database so they could be easily extracted. For example, for linsting best reviewed items etc.

Basicaly, I need something to assign a numerical value to the post, stored in DB.

I could use some post rating plugin for user’s grades, but I need something for author’s grade.

Any ideas much apprecieated.