ChatWing is a free service that you can use to put a live chatbox into your blog or website. The service actually creates a micro social network that you can use in your blog - that's where the chatbox comes in - or as a stand-alone service. When you sign up for ChatWing you're taken to a screen to create your ChatWing network. On that same page you can customize and test your chatbox. After you have settled on the design of your chatbox you can grab the embed code to install ChatWing on your blog or website.
Applications for Education
ChatWing could be used as a backchannel tool embedded directly into your classroom blog. By embedding it into your classroom blog anytime you want to use a backchannel students just have to visit the blog instead of having to visit a new URL.