Weme via Amazon offers the Alxum 24-watt Dual-Port USB Ultra Compact Car Charger in Black for $7.99. Coupon code "W5KMH8EO" cuts it to $6.99. Plus, Prime members bag free shipping. That's tied with our November mention, a buck off, and the lowest price we could find. It can charge two devices simultaneously and features a 4.8-amp maximum output. Deal ends January 15.