title_body: What does the extremely fragile glass do in Kindle3's pearl e-ink display?
upvoted_answer: E-ink displays have to be mounted on a surface. In this case I assume that was done on the glass. This keeps the E-ink nice and flat (good for equal visibility of all pixels) and for extra reflectiveness of ambient light, if the glass is part of a mirror (as it seems to be).
  
  The display is actually a thin film transistor array and my guess is that if the supporting glass breaks, some of the circuitry of the thin film get ripped. A single rip across the width or height would make addressing the film as an array impossible.