A katana is a type of other-worldly sharp object used for slicing things very quickly and violently. Found exclusively in heaven and retail stores, katanas come in all sorts and varieties of colors, all of which are black. Recently Apple has released an all-new white katana which is USB compatible. Sony offers a dark blue katana in a Hello Kitty style. Each of these katanas only have a battery life of fifteen minutes before needing to be recharged.