Today only (12/9 - just 15 more days until Christmas!) you can save 20% on select Kindle e-readers and Kindle Fire tablets.  Choose what suits your needs best: Kindle, from $56; Kindle Fire HD 16GB, from $136; or Kindle Fire HDX 16GB Wi-Fi, with a perfect-color HDX display, ultra-fast processor, and the revolutionary "Mayday" button [...]