Update: This deal has expired.

Amazon has the WD 1TB My Passport portable hard drive for $43.40. This drive has spent much of the last three months fluctuating quite a bit in price. It has sold as high as $60 and as low as $45 while also going out of stock a couple of times. It definitely seems to have a limited availability, which means this deal will probably be gone by the end of the day and the item might sell out again. At the moment though, it's selling for its lowest price ever.

This deal price is only available to Prime members. The hard drive is formatted for Mac machines and works with Apple Time Machine. It has a USB 3.0 port. It also has built-in hardware encryption and can leave a "report if found" message should you happen to leave the hard drive containing all of your valuable and private data lying around in a shopping mall.

The device has a 3-year warranty from Western Digital.

If you're a Windows user desperate for storage, you could buy this drive and reformat it or get the Windows-compatible version of this drive or the Seagate Backup Plus Slim 1TB. Neither is really on sale but they're both very good drives that won't let you down.

See at Amazon