Nomad ChargeKey is a portable USB adapter that fits on your keyholder
The Nomad ChargeKey is a tiny cable adapter, not much bigger than a regular key. In case you are on the go and the charger for your, say, iPhone 5 or HTC One are not nearby, the Nomad ChargeKey allows you to plug your device into any compatible USB port in order to charge and sync it simultaneously.
The Nomad ChargeKey outputs as much as 3.1 amps of power and supports USB 2.0. The middle section of the accessory, which is "built to hang and bend", is made of rubber and is touted as being quite long-lasting – in fact, the Nomad ChargeKey comes with a full life-time warranty.
Both the Lightning-to-USB and a USB-to-microUSB adapters are priced at $25 (free worldwide shipping included), but are currently out of stock. You can check them out on the manufacturer's website at the source link.
source: Nomad via AppleInsider