Staples offers the Urge Basics PowerPro 2,000mAh USB Keychain Charger
, model no. SQCHGRCHAIN-WHT, for $4.99
. Plus, Staples rewards members bag free shipping
. (Not a member? It's free to join
.) That's the lowest total price we could find by $1. It features a 5-volt/1-amp input and output and a lithium-ion battery. Deal ends on October 13.