The Targus Notebook Chill MatTM is a simple device that provides external cooling for notebooks. It consists of of two metal plates between which a pair of 1500 rpm fans are sandwiched. The fans are powered by a cable that connects to the mat on the middle of the right edge, and any USB port of the notebook being cooled. The cable includes a delicate switch in case one needs to turn off the fans.
In my testing with a 15.4" wide screen notebook, I found it to be good at cooling over extended use for several hours. No more burnt laps! As an added bonus, the fans are really quiet. Perfect for any surroundings. The device weighs about 15 oz (425 g) making it fairly portable. The mat consumes about 1 W of power. At 20 USD, this is a great buy.