Wordpress Chat Plugin

I have 4-5 wordpress Websites for the same company but need a single point for the operator to chat with the client. Does any one have a solution in mind as having them logged into 5 different consoles doesnt make sense.

Thanks in advance for your help and responses!

If you want to host it yourself, LiveZilla is a good solution amd can be easily integrated into your existing WordPress sites. Free for 1 operator. http://www.livezilla.net/home/en/