As one of its daily deals, uNu 1,700mAh Portable Battery Pack for iPhone 4/4S, model no. DX-1700B, for $24.57. Coupon code "FreeYugBuck" cuts it to $23.57. With $5 for shipping, that's the lowest total price we could find by $11. It includes a transparent screen protector, cleaning cloth, and charging cable. Deal ends February 5 at 6 am ET.