Amazon.com
The Motorola dual-slot rapid desk charger can simultaneously charge your phone and back-up battery.
Small LED lights let you know when your phone is fully juiced, and the charger's diminutive measurements won't take up a lot of space.
Amazon.com Product Description
This powerful charger has two ports that can rapidly charge two batteries in 3 to 5 hours. The rear port discharges batteries to prevent memory damage, and the USA quality-assured circuitry prevents damage from power surges. It is powered by plugging an AC adapter into a standard wall outlet, and contains automatic cutoffs that prevent the unit from overheating or overcharging. The AC adapter for this charger is sold separately. This charger does not support auxiliary batteries.