If you are somewhat in astronomy and space, as I am, you might fall in love with the European Southern Observatory.
They provide an overwhelming library of images and videos. Many of them available as desktop wallpapers in various sizes.
Among, you find images like this 340-million pixel image from Paranal
or the 108 200 x81 500 pixels image from the milky way. You can download the 25 GB file or just check out the zoomable view.
In case you fall in love with any of the views you might want to order a mounted image in their shop.
Definitely a rabbit hole.