Disqus is a realtime commenting system with a focus on clean design, great UX and building a community with your commenters.
Pro Clean, minimalist interface & design
The Disqus design is minimalist and is broken down into three tabs - discussion, community and My Disqus.
The discussion interface provides the usual elements, but with unique features like visual indicators of live actions, such as new replies and even when another user is typing. It's possible to sort discussion by new, old and best.
The community tab is designed to help connect commenters together to form a network that keeps them coming back. It is also a great source of traffic from external sites.
My Disqus helps users quickly keep track of activities in their network as well as manage notifications.