Shoutbox

I think the better option would be to use Plus! toasts for notification, but modify the xml containing the toast interfaces so that the toasts are larger (if you really want you can make it bigger than the screen, but i think that's pushing it a little too far).  Personally I'm not sure which DLL you would need to reshack or where abouts it is or even where to put it afterwards and feel it would be best if someone else answered that part, but I can inform you that it is possible to give larger toasts by editting a file, you'll just have to wait for someone else to help you out with what exactly to do.