The world&rsquos newest thinnest tablet is a 6mm marvel. The 8.5-inch alu­minium case houses a 2560x1600 pixel OLED screen &mdash smashing display. The really fun part, though, is the Intel inside not the chip, the RealSense 3D camera. The main 8 megapixel camera is joined by two 720-pixel ancillary ones in a strip, together producing a composite image. ($400, dell.com)