Cellular Factory offers the Notebook Cooling Balls in Black, model no. 32477-B07-146, for 99 cents. Plus coupon code "1W99VR" bags free shipping. That's the lowest total price we could find for this item by $2. (We've seen similar models for as low as 39 cents in the past.) These devices attach to the bottom of your laptop to create space for air flow. They also feature a hook-and-loop design that purports to be anti-slip. Coupon expires August 1.