Cheapest on SI is $53 + delivery
Functionality – Can power and/or charge a laptop and a USB compatible device at the same time (USB charging cable not included).
USB Fast Charging – 2.1amp charging for the fastest charge of Tablets and Smart-phones.
Mobile power – A perfect solution for laptop users on the road, small enough to leave in place in the car to ensure your always ready to go.
Quality and performance – Built to notebook manufacturers' standards for worry free operation.
Guaranteed Compatibility – Rigorously tested to ensure compatibility with major manufacturers.
There's an even cheaper one branded Kerio for $15 that I saw today, I was interested until I saw that it was a car charger.