Sitting pretty with your 2560 x 1440 Apple Thunderbolt Display? You could put that screen in your pocket if Toshiba has its way. The company's just announced a prototype 6.1-inch display with a crazy 2560 x 1600 resolution, or 498 pixels per inch — enough pixel density to make a Retina Display-class screen even out of the controversial PenTile matrix. Mind you, Samsung's already building that same resolution into a 10.1-inch screen with 299ppi, but a little competition sounds fantastic; we want our portable desktop-grade computing experiences sooner rather than later. Hit up our second source link for a full-size image.