AnkerDirect via Amazon offers the Anker Astro E5 15,000mAh External Battery Power Bank in Black, model no. AK-79AN15K-BA, or White, model no. AK-79AN15K-WA, for $49.99. Coupon code "ASTROE5S" cuts it to $42.99. With free shipping, that's $97 off list and the lowest total price we could find. It features dual USB ports for simultaneously charging two devices, four status LED lights, a flashlight, and USB cable.