CSC chat support
You can almost only raise a ticket with CSC support if you can contact chat.csc.com, so you are usually SoL if you can't even get to that.
However, although we have corporate messaging (Skype, shudder); which those agents can use, you have to use the chat window to contact them. Time for them to respond can easily exceed an hour (my record is 3:35) and then, when they finally respond you have about 5 minutes before they give up and close the session.
However, the chat window has no visual notification, let alone an audible one, so you have to sit there with the window open without taking your eyes off the screen for more than a couple of minutes.