Plugin for “Was This Helpful” at end of post?

I’d like to use a WordPress instance as a product help & faq platform.

I’m wondering if there is a lightweight plugin that provides a “yes/no” voting option at the end of a post, to which I’d use the question “Was this post helpful to you?” I can then go into the admin panel to see the total number of yes’s and no’s per post.

Does one like that exist?

I’ve found a multitude of “Digg-like” up/down plugins, but they are far too complex for what I’m looking for. I’ve looked at Vote-It-Up and WP-Polls, which both seem like they can be hacked to accomplish what I want, but I wanted to first check to see if there was a ligher weight solution out there.

Thanks in advance for the suggestions.