What is “small”?
As it’s a current subject in the german openHAB Forum…
The displays are ePaper Displays, so very low energy consumption.
You will need an AP (AccessPoint) to send pictures to the displays (using Wifi).
The AP gets text, format and so on to create the picture and then to submit to the display.
I’m still thinking about use cases to “excuse” for buying some of these devices - and I have some old eReaders to “recycle”… 
Try search for Wall-display.
To my knowlegde, there is no plug&play ready solutions.
What you need is some sort of “tablet/screen” device, and then build the UI yourself, for this specific device.
The tablet can however be anything else running a browser.
And then there may still some hassle with it, specielly around the kiosk/fullscreen settings as well as power for the device. I´m struggling myself with a Android tablet running Fully Kiosk browser and the mainUI. I´m close to throw it all in the trash 
Has anyone managed to get this to work with openHAB UI?
Sort of
Ink e-Paper and ESP32 connected to oH seems to be a very nice DYI Project. I will take it on my todo list.
Not small, 10.5" 1980x1200px IPS Display
30 Euros 2nd hand market
Blackview Android 12
Works very well but more like a kiosk display
Solong
B
I did something similar: I built a family calendar based on Google calendar with an ESP8266 and an ePaper display. And that wasn’t that difficult. There are special variants of the ESP8266 with an interface for an ePaper and me as an absolute beginner just needed some days to understand several code examples I found online to combine everything to a working solution. And as I also build some devices with an ESP8266 using MQTT to communicate with OH, it would be quite easy to realize something like what you want with just some lines of code. ESPhome could be an alternative but for such simple things I would judge you will get to faster results if you just go the manual way before getting comfortable with such a quite complex thing, having its advantages if you want to do more.
Talking about energy consumption the ESP8266 has the nice feature to switch off itself and reboot after a predefined time. My calender uses this to just power on every hour to get new data, write it on the ePaper and then switch off again.
Nice one, but to big for each room and simple information. I got similar with an old 8 zoll Tolino Android Tab. The problem with Tabs IMO is the display, which have to turned on. Apps with movement sensor via camera, as i searched for 5yr., wasnt that good. Always on is to much power consumption.
edit: Blackview is an chinese brand, which i not trust, so no option for me
That sounds good. I see same examples and configurations. I think its possible for a beginner. I got it on my list. Do you have photo from the ePaper, just as example how it could look like?
what about amazon kindle? its cheap, it has a browser, e-paper screen… just open OH page in a browser
Here you go:
My GUI is quite simple. I read the date via NTP get the calendar entries for today and the next two days and display a day-entry, followed by the entries, if there are entries for one of these dates.
Up to now my device is USB-powered, but this is not necessary.
Thx for showing. I read and view some ePaper DYI and would just buy all components and start with it, but i got not time, but it sounds interesting and with a manageable effort it could be nice.
Just as a tip what I did when I had a similar challenge:
From ELV there is a display available which is already supported by openhab via the Homematic-binding (and of course a Homematic-Bridge!): HM-Dis-EP-WM55
Fits in a flush-mounted box and look pretty professional 
Personally I hung an old Samsung tablet up above a wall outlet, disabled the screensaver, made a custom page, plugged the charge cable into a usb port on a plug with 2 usb ports built into it so I can still use the outlet, and I was done… The tablet was configured for Wifi and had no cell service, so no recurring costs other than the power. Plus I can use it in a pinch to control the house too.
I have some of these, diy or premade panels
Sonoff has a neat display that can be flashed with Tasmota firmware and integrated with Openhab using MQTT (Sonoff Product Site)
Check out this post: NSPanel
A detailed documentation of what you need to do is available here: https://github.com/alfpf/NSPanel-setup
Note: Its very much of a DIY project so be prepared to spend some time, but I have two of those panels in my house configured showing temperatures and weather forcast on the main panel, and sub panels to control light switches. You can control e.g. the dimming level using OpenHAB rules and I also use rules to trigger the warning icons on the panel.
It communicates with WiF, only wädownside is that requires power. I solved this by removing the bulky adapter on the back of the panel and instead used a thin wire to a small AC-DC comverter I hid behind the nearest outlet.
I use Sunfounder touch screens, they work well. Just install a Pi on the back and use a browser to access
if it’s just a simple value like the temperature or similar, you could also use Matrix Display like LaMetric Time or the Ulanzi TC001. I’m using both to show the Outside Temperatur obtained via MQTT. La Metric is quite expensive an limited to one DIY App. the Ulanzi TC001 is far cheaper but you better flash it first with AWTRIX Light AWTRIX LIGHT , which will allow you to deploy custom apps. to get simple values on the display, you need modify the payload to device specific json and publish it to the MQTT topic you configured as custom app. I do this with Node-RED in between, which subscribes to the values published via Openhab Rule to my MQTT Server, converts the Payload in expected JSON and publishes it back to the new Topic configured on the device.
Sorry for hijacking/advertisement in this thread but I also created a binding for the ulanzi clock: Awtrix Light Binding
Maybe you want to give it a try 
It would be great to have some more users testing this 
Please keep in mind that the great Ulanzi TC001 (I own two myself) is no wall display
But at least it’s nice for a shelf
