Ebay offers WD - easystore 18TB External USB 3.0 Hard Drive - Black for $300 (reg $516.99) with free shipping.

Product Description:
Store and transfer files with this WD easystore desktop drive. The 18TB capacity accommodates the largest games and applications, and the transfer rate of up to 5Gb/sec. lets you quickly share large files. USB 2.0 and 3.0 connectivity make this WD easystore desktop drive compatible with a wide range of computers and other devices.