More than any other piece of technology I own - phone, laptop, watch - my Kindle makes me happy. A big part of that is the display and it's paper-likeness.
I just wish I could figure out a power scheme that would make it worth my trouble to use them as information radiators. Perhaps rechargeable batteries.
Displays like this would be a good candidate for wireless power schemes, but they aren’t sited in places with a good set of power scavenging options. Maybe solar.