-All
Cheap? Should be.
These screens, as dukestreet pointed out, are very simple. No Backlight, back polarization filter, rigid LCD layer, front polarization filter, and protective layer.
Essentially it's just two layers, the back substrate that the pixels are printed upon, and a front layer to sandwich-protect.
Additionally, to create such a screen, what wil be the back layer is run through an unmodified inkjet printer with special ink. The CMYK of printed color is replaced with RGBC ("C" for conductivity circuitry). Takes about a minute to make a screen (8.5"x11"), then you just attach the ribbon cable and plug 'er in.
The main issue that these screens have had is the lifetime of the color components of the pixels - namely blue which, at last update, only lasted about 2,000 hours. This is why LCD's rule the roost for now.
But once they get up to the lifetime of LCD's expect that to be the tipping point. Then we'll get stuff we've never seen before - animated billboards, buildings that can change color, windows that can have a TV imbedded in them, and of course practical PDA-Celphones

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