You know how it works: You're groping around blindly in the dark for your tent zipper when your foot catches your tent line and you go down hard on a log with broken, protruding branches. It hurts. In fact, it really, really hurts. You don't want something like this to happen to you in the middle of the woods.
Enter clip-on LED lights. You can mark those death cords around your tent -- and any other dangerous stumps, sticks or lines for that matter -- with these small lights, so you won't trip over anything in the middle of the night.