The E-Ink technology is a reasonably new technology with a promising future, widely commercialised by the E-INK company. The content displayed on the E-INK (also known as E-Paper) display does not degrade when exposed to direct sunlight, the display actually behaves like real paper; it is more readable when there is more light hitting its surface.
This E-Paper Display has a 1.54" screen (200x200 dots).