Nomad ChargeKey, a lightning adapter that fits on your keyring

I’d definitely like to take one of these for a spin. There have been a number of times when I was on the road, my iPhone was running low on charge, and I didn’t have the right cable on hand.

My only concern is durability. Both ends of the cable are open to the elements and the cable will be riding around in your pocket, picking up all manner of little gunky bits and debris. Still, a terrific idea.