VIZ:

        On the player select screen, type "WHAT A LARGE SET OF BOLLOCKS" and
        press 'RETURN'.  The background should now turn white.  Now on that
        same screen, press a number '1' through '5' (on the main keyboard)
        and press fire to skip to the corresponding level.

        It may also be "WHAT A GREAT LOAD OF BULLSHIT"