Meritline offers the OCHO 5,000mAh Backup External Battery Pack Charger, model no. MLG-4096OT, for $29.99. Coupon code "MLCKS21UNL1" cuts it to $19.99. With free shipping, that's the lowest total price we could find by $10. It's compatible with most phones (including the iPhone), tablets and other 1A-compatible devices. It features a built-in LED flashlight and microUSB connectivity. Coupon expires after 200 uses.