Today only, until 8 pm ET, Newegg via eBay offers the Seagate 4TB Backup Plus USB 3.0 Portable Hard Drive, model no. STDR4000900, for $109.99. Apply coupon code "C15LIMITEDTIME" and checkout through PayPal to cut that to $94.99. With free shipping, that's the lowest total price we could find by $28. This drive is compatible with Windows and Mac and features an 18" USB cable and pre-loaded backup software.