The WP Voter plugin for wordPress is extremely simple to use, and enables you to quickly and easily add drop-dead-simple visitor feedback to all your posts, pages and comments. It does this in the form of adding simple thumbs up and thumbs downs icons in the relevant places on your blog.
When someone clicks one or the other icons, it registers the vote, notes the IP address and looks to see if it can’t match up the IP with someone who’s left a comment on your blog so you know who it is where possible.
This gives you and other visitors to your blog a fast idea whether the particular content is liked or not.
The plugin only allows one vote per IP address unless the visitor is logged in. This then allows multiple people at the same location to individually vote on the content.
As an example of a killer usage of this plugin, it would be ideal for use on a membership site where the members are paying for content. You would see right away which content is popular and well liked and which to steer away from.