You get to camp later than you meant to. Poles in one hand, a stake bag in the other, and it's already dark. Hold your hand up to the sensor on the right temple and all four lights come on — gloves on, hands full, nothing set down. Do it again and they go off.

Two in the morning, tying a hook with wet hands. Look down at the line and the line is lit. Look at the net and the net is lit. A torch lights where your arm is pointing; this sits on your face like glasses, so the light goes where your eyes go.

A bar light points where the bike points — coming into a bend, it's still lighting the straight you just left. Turn your head into the corner and the corner is lit. Both hands stay on the bars, and there's no band around your head to tighten or knock loose.