Sunvalley Brands via Amazon offers the RavPower 22,000mAh Portable Battery Pack in Black or White for $31.99. Coupon code "7THDVPYE" cuts the price to $29.99. With free shipping, that's $2 under our October mention and the lowest price we've seen. (It's the best deal today by $10.) It features three USB ports and is compatible with a range of devices. Deal ends January 23.