The keyboard is still one of (the?) most efficient mechanisms for interacting with a computer. Many applications that aren't text-entry centric can increase user productivity by using keyboard shortcuts for functionality (think of a video editing application: fast-forward, back up 2 sec, mark a segment, etc...). However these function suffer greatly from discoverability issues. If you could put the functions directly on the keyboard, you'd be able to find these shortcuts much faster, and be able to be more productive. Once you've learned the shortcuts, the e-ink becomes less useful, but during that initial discovery (and memorization) phase, it would be extremely helpful.

if you allow enough alternative keyboard layouts for exotic unicode characters then you probably won't have muscle memory for it. So cycling through blocks with hunt and peck might be useful for rarely used characters.

Or as accelerator key hints for application-specific keyboard shortcuts for applications that you don't use on a daily basis. Instead of having to dig through 3 levels of modal dialogs or menus you could just look at your keyboard to find the right shortcut.

First step in playing a PC game is to go into options and try to memorize the controls. This could be useful for gaming or specialized applications like CAD.

The first step is to rebind the controls because they're all wrong. Even so, I do occassionally forget what went where. So a thing like this could be useful. Of course it would never be supported unless it were common, and I don't see it becoming common.

Even with cad you tend to memorize, that and it doesn't (my exp is limited to autocad) use off hand chording too often. mostly its keying in short commands, such as 'li' or 'c', followed by an 'enter' action key (often space bar)

Perhaps it could be more useful for apps without a cli, like a DAW software package?

Nah. Displaying keyboard shortcut hints on screen next to the button at mouseover, which many applications have done for at least a decade, is much more efficient. Constantly looking down, looking up again, looking down etc. is terribly inefficient.

I think there's better use for screen estate than placing buttons on them when you already have a hundred or so buttons available at your finger tips.

>And wondering what an E-Ink Keyboard is good for in the real world

Multilingual people who want to type in different languages easily?

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