They say there are a 1000 uses for a good knife, meaning there’s likely unlimited potential for a batarang knife.  This twin blade Batman folding pocket-knife fits comfortably in the hand or pocket and easily obliterates villainous tapped boxes and stubborn knots.  The combined 11″ stainless steel blades move independently and can be opened together or separately.  A locking mechanism keeps you from losing any digits.  Not bad for less than 10 bucks.