I'm still waiting on some clever folks to figure out a practical hybrid LCD over backlit e-ink display. There seem to be no major technological hurdle, just the practicalities of doing so, and affordably. Done properly it would be the perfect display technology, readable from darkness to full sunlight, suitable for high-contrast reading as well as full motion video, and using no power when not lit or refreshed (but still displaying whatever was last rendered to the e-ink layer). Even a colour LCD over a monochrome e-ink layer would be potentially compelling, IMO.
Transflective displays seem like a dream technology for outdoor and indoor use.
Unfortunately, large displays seem to be unavailable, at least not at anything resembling a reasonable price. I wouldn't mind if it was monochrome in sunlight.