A few years ago I used to read comics books on a Raspberry-Pi/Kodi TV box. Once in a while I'd see something that looked wallpaper-worthy. I'd zoom/pan it to get a nice frame (as accurately as the remote control would allow), capture the screen, and get a wallpaper-sized image for the screensaver. Here are 100 of those, in Untrue Color™.
This Psycler fork is couch potato ready™: It's already in a shuffled slideshow. Just click on the image to switch to fullscreen.