This command will hide the UI, including the console. To enable the UI again, type the command into the console again - note that the console hotkey will still open the console, even though you can't see it (when the UI is hidden).
togglemenus
ToggleMenus
The above command will hide the UI. To disable the effects of this command, hit the button to open your console, type this command and hit enter (the console won't be visible, but it will still register the command).