Lugging around an external drive that weighs more than your MBA kind of defeats the purpose of buying a lightweight laptop. Luckily, Western Digital's latest My Passport drives can hold a terabyte of data but tip the scales at less than a pound.
The Studio connects with FireWire800 for lightning-fast (though not Thunderbolt-fast) data transfers and the ability to daisy chain other FireWire peripherals or hard drives. It also features 256-bit hardware encryption. The My Passport for Mac also has a 1 TB max capacity but does away with the display and FireWire in favor of the smallest footprint ever for an WD external drive —less than 3/4-inch thick—and is powered through the USB 2.0 port.
Both drives are formatted for Mac and are compatible with Time Machine. The My Passport Studio runs between $130 for the 500GB up to $180 for the 1TB. The My Passport for Mac costs between $100 and $130 for the same data capacities. Both are available on the Western Digital website.