n. Any very unusual character, particularly one you can't type because it it isn't on your keyboard. MIT people used to complain about the 'control-meta-cokebottle' commands at SAIL, and SAIL people complained right back about the 'altmode-altmode-cokebottle' commands at MIT. After the demise of the space-cadet keyboard, 'cokebottle' faded away as serious usage, but was often invoked humorously to describe an (unspecified) weird or non-intuitive keystroke command. It may be due for a second inning, however. The OSF/Motif window manager, 'mwm(1)', has a reserved keystroke for switching to the default set of keybindings and behavior. This keystroke is (believe it or not) 'control-meta-bang' (see bang). Since the exclamation point looks a lot like an upside down Coke bottle, Motif hackers have begun referring to this keystroke as 'cokebottle'.
See also quadruple bucky.