Compiz can do it with any classic key combination you like... Still Gnome "Key Bindings" should be grown up to something more powerful in terms of programmable actions list. Not everyone want compiz, after all. In KDE things look a little more powerful, yet complicated.
Why not let "Key Bindings" to have custom commands fed to command line with a key shortcut, too? Why going for primitive copy? Make it better, more flexible, more powerful, more customizable, yet keep it simple and sensible while in default mode! Vote for Ctrl+Esc for default, and against cloning MS unconfigurable, violent, dictating style in general.