At these levels there is almost no profit margin left in the hardware business. A $45 tablet is cheap enough to be an impulse purchase at the check-out line in Best Buy. A $45 price puts tablets within reach of a whole host of other activities not traditionally associated with computers. Tablets could be used by waiters in restaurants. By mechanics in auto body shops. By every nurse in a hospital. By pretty much any category of work that today needs a computer but where PCs are too expensive to be deployed. These are also devices built entirely for commercial reasons, no government backing, no academic sponsor, no proof-of-concept.