This plugin allows your visitors to authenticate using any OpenID account such as Google, Yahoo, or AIM and then comment on your posts with no need to complete a registration form. The idea behind Friend Connect is to have a unified presence across any number of blogs and sites hosted by various services. This eliminates the need to register and manage multiple, separated accounts on different sites. It can be seen as a Facebook Connect competitor of sorts, though the two tools have different target audiences and goals. The main draw of Friend Connect is the ability to leave a comment that is connected to a real account, as opposed to just leaving an anonymous one, without having to create a new one. Installing the plugin is as easy as any other WordPress plugin and requires you to sign up your site with Friend Connect and then download and install it. Detailed instructions can be found here.