External storage systems with an eSATA interface offer great flexibility. Single drive enclosures are great for high-speed solid state drives (SSDs) or hard drives. Many storage enclosures are portable, and include swappable drive trays that are perfect for managing daily backups and multiple projects. Some enclosures, like Sonnet's Fusion D400QR5 and Fusion F3, feature hardware RAID controllers that enable multiple drives to communicate with the host adapter through one cable. Through its two ports, Tempo SATA 6Gb/s ExpressCard/34 can handle up to eight drives.