As a reader discovered, eCase via Amazon offers Prime members the Kmashi 10,000mAh MP816 External Battery Pack for $11.99. Coupon code "6ACUX5E9" cuts it to $9.69. With free shipping, that's $2 under our mention from five days ago, the lowest total price we've seen, and a current price low by $5. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $6.55.) It features dual-USB ports, four status LEDs, and compatibility with most USB-driven devices.