As much as I’d rather not give Bezos any more money, these look really useful.
Good size for sticking inside DIY cases, runs on 12vdc so it would be easy to convert to Eurorack power (or any other modular format really, since stepping down from 15v is so simple), small enough you could stick a couple of them on the top of a video mixer to use as little preview monitors. I’m going to grab two or three next paycheck just to have around when I need them.
i have those velcro’d on to my v4, pretty useful for those mixers that you need to see the menu on a screen. the image isn’t really good enough for a final preview out or feedback imo but for the size they are really nifty.
Yeah, menu preview on my Vidionics switcher is exactly what I was thinking of. I’ve got a 7" portable LCD for final output preview and a 16" 5:4 LCD TV set and couple small CRTs for feedback, so for me the plan for these is once I’ve got a few more things built I’m going to center all of it around a normalled RCA patchbay I’ve got kicking around, so I can rerout sources and feedback loops on the fly, and having one or two of these on the patchbay to preview what’s happening at other points without having to rout it to an output would be handy.
No need to Lex Luther involved! Plenty available on eBay, Banggood etc.
3.5" one seems to be LQ035NC111 which is used in many Arduino / Pi hats. Same as repurposing a laptop screen you can search for a controller board to go with a model of LCD:
LQ035NC111 controller board ~3eu
LQ035NC111 LCD ~7eu
True, but it’s nice to have a plug and play option.
Now if only I could find a halfway affordable 4" color CRT to stick in a box with a camera and make a low rent analog rescanning setup. A 1080p HDR camcorder pointed at a decent CRT seems like the ideal way to upscale this sort of stuff. The camera is all set and I do have an old Amiga monitor but the color is kind of off on it, and with a 12"-or-whatever CRT the whole setup would be way too bulky.
Just about every small enough monitor I see is monochrome and too expensive. I need to find one of those little portable TV sets from the late 80s, I guess.
Not that Jack Ma is much more likeable than Bezos, but Aliexpress is usually way cheaper than Amazom with stuff like that. 
for example: https://de.aliexpress.com/item/4000274106633.html
usually free/cheap shipping (and at least in germany no customs duty if it is < 20€ 
)
Yeah, I use Aliexpress sometimes, to, but in this case the shipping cost/time didn’t work for m. That looks like a good option, though.
The one I posted is working well as a monitor out for my little Vidionics mixer, it’s big enough to read the menus easily but small enough that it doesn’t take up any extra space.