I've seen these portable e-ink monitors available for nearly 10 years now, but this one seems to be the first that's responsive enough for general usage, which

I've seen these portable e-ink monitors available for nearly 10 years now, but this one seems to be the first that's responsive enough for general usage, which is a big step forward. Out of curiosity, if anyone here has one, what do you use it for? There must be something people are using them for if they've been a product niche for so long, but I can't think of what I would do with a standalone 13 inch e-ink monitor.