Rhino Laces are gunmetal-tipped boot laces purported to be totally indestructible. The makers claim that they "cannot be burned, cut, sawed, chopped, destroyed, or broken, or we will replace them for free."

I haven't tested them myself, but I've seen reviews saying that they're even tougher than paracord, which is pretty impressive. If that's true, these laces would be perfect for outdoors excursions and might even come in handy in a pinch, say, when you need to bind things together or strap them down onto a truck bed.

A set of Rhino Laces is $20 on Amazon, and they've got a few sizes to choose from.