Energenie ChargeGenie: Universal MicroUSB Charger for Smartphones – CES 2013
The ChargeGenie is a 1400 mAh or 2000 mAh power pack. A sticky surface on the ChargeGenie allows you to stick it right on the device – Blackberry, Android or even an old flip phone with a microUSB connector.
When done charging, retract the cable back and keep the charger on your phone – or just put the charger away. (Energenie UK site)