Story : http://www.pcworld.com/article/2036197/western-digital-rolls-out-ultra-slim-5mm-
The drive towards dirt-cheap Ultrabooks is getting a big boost with the release of Western Digital’s new ultra-slim spinning hard drive, a barely there piece of hardware that is even thinner than the iPhone 5.
WD’s new WD5000MPCK, as it's clunkily called, is a 500GB traditional hard drive that measures just 5mm (0.20-inches) thick. Part of the mid-range WD Blue lineup, the hard drive is 0.10-inches thinner than the current iPhone and around half the depth of typical 2.5-inch notebook hard drives.
WD says it is able to offer such an impossibly thin hard drive because of advances in shock protection and a motor shaft that can reduce internal vibration and stabilize drive platters. Beyond depth and capacity, WD’s new ultra-thin hard drive features a 5400RPM rotational speed, 16MB cache, 6Gb/s SATA interface, and weighs 0.16 pounds.
What the new hard drive loses in bulk, however, it makes up for in price with an MSRP of $89. At less than $100, the new hard drive is still really cheap, but comparable 9mm-thick drives with a faster rotational speed of 7200RPM are priced around $50-$60.