You can say that the all new WD Blue and WD Black 2.5-inch drives were specially manufactured with notebooks and Ultrabooks in mind, where being a mere 5mm thick, it would translate to sleeker notebook and Ultrabook designs down the road. The thing is, will the other components and parts of a notebook or Ultrabook be able to achieve such levels of miniaturization? This slimmer design is touted to lower weight by up to 36% compared to the traditional model, not to mention boasting of reduced noise during operations. The 500GB WD Blue 5mm will retail for $89 a pop, while versions of the WD Black 5mm SSHD are said to ship to PC manufacturers, leaving us in the dark concerning its capacity and costs.