Simple WordPress plugin for up/down voting on posts and comments.
UpDownUpDown provides two template tags for adding up/down voting for any post or comment. Anonymous guest visitors can either be allowed to vote (tracked by ip address) or be denied voting and shown a view-only vote count badge. Votes are registered on the server without refreshing the page.
Fork the Github repo: https://github.com/davekonopka/updownupdown
This plugin was initially developed as a project of Wharton Research Data Services.