Simple Live Support Chat.
client: java applet with a memo field (to show the chat) and a edit text box (input)
Operator (Win32 application): When I run it notice the web page the service is online and then app. remains minimized. If a client opens the java applet client the windows app. brings to the front and it notice the web page the service is busy, the chat begins... When the client disconects or a timeout expires notice the web page the service is online again.
Note: Maybe you can replace the java applet with a Flash plugin
(excuse my english)