Another option is an actual USB hub, although I tried that (see Lexma) which was a powered hub and I ended up with a broken inaccessible partition.Also the price is about the same as two “fat” 5 TB passport drives. Also, according to this cnet review, if the drive is plugged into a USB 2.0 port then the built-in USB 3.0 hub does not work correctly, and may not detect what is connected to it. … one option is to use a Seagate Backup Plus hub, big (at up to 10 TB) but noisy, or at least noisier that passport external disks).Daisy chaining USB 3.0 passport disks – not possible due to them not having two USB ports (see Is there a way to daisy chain USB3 external hard drives?) and I don’t have a hub, although….My 15″ Santa Rosa (2.4 GHz) MacBook Pro is seriously limited with its two USB 2.0 ports.