As expected, wearables are all the rage at CES 2015. And while most of them are about looking fancy and sending useful notifications to your wrist, there are also others whose goal is to keep you feeling healthy. Enter NeuroMetrix Inc.'s Quell, a wearable that attaches to your upper calf and promises to make chronic pains go away within 15 minutes of putting it on. Quell's OptiTherapy electrode-driven technology uses non-invasive nerve stimulation to make this possible, allowing it to provide "100 percent" prescription-free relief to anyone who uses it. NeuroMetrix says that Quell is capable of relieving different types of chronic aches, from nerve pain to lower back problems.