I discovered this by accident for one of my webs social (needed a link directory for the site) which is smartchatbox.com, they are free and paid, many styles and colors. You can create a chatbox and add it in the bottom corner to the html of your header or your footer, and you will be given a chat icon bubble and you can click it and open it for chat. You have to sign up on it, but it works if you don't want to use the other chat/chat rooms.