There are alternatives that are cheaper:

https://www.amazon.com/waveshare-7-5inch-HAT-Raspberry-Consu...

Thanks for the link, that looks interesting. I have to see, where I could buy it (Amazon doesn't ship it to Germany). I will certainly check this out for tinkering with my Pie. Of course, I wouldn't buy the ReMarkable just for using it as a second display, but that would be an added value, if it could be done with some more software I can install on it. My main usage would be as a reader/note tool.

Waveshare have lots of such screens, big, small, some colour: https://www.waveshare.com/product/displays/e-paper/epaper-1....

Doesn't mean, I wouldn't use it for its advertised purposes too. But I really would like an eInk display as an add-on to my computer - unfortunately, the Kindle is not so open.

Would also be great as an extra screen for e.g. man pages while you are working on your main screen.

There is also a smaller, cheaper, and less slick device at Crowd Supply made from recycled Kindles.

https://www.crowdsupply.com/e-radionica/inkplate-6

15cm, 800x600, 8M RAM, 4M flash, wifi/btle, usb/sdio/i2c, 3 capacitive-touch buttons, battery charger, microSD slot, GPIO pins, and is programmable in microPython. Three-bit greyscale pixels.

(I don't have one.)

I don't know if the remarkable does this, but the onyx boox max 2 has an hdmi input (on some tiny connector.) I've used it from my laptop as a second screen, and displayed emacs and xterm on it. Really need to craft up some kind of bracket to use it as an outdoor primary laptop screen...

then get one of these for £50 https://www.amazon.co.uk/Waveshare-HAT-Resolution-Electronic...