How to add Top Commentator in blog?

As you can see I have more than a blog and not all my blog is having the Top Commentator. Do you have it at your blog? I know some of my friends still not interested in blogging. Anyway, I know some blogs are not having top commentator widget. I like you to check out on how to add Top Commentator in your blog. You can also learn blogging tips at Makoy's blog.