Hi!
Back when I first started out with 3D Games, I had most skyboxes for my projects from an awesome website called redsorceres dot com. The owner shared a lot of models and textures and it was an all around cool site.
However, it was part of that hobby era of 3d content from between the late 90s and mid 2000’s..and like the vast majority of these sites, its now gone. However, I found a few cool people who archived the skyboxes at least. I took the liberty of providing a mirror myself too.
Now these skyboxes are on the lower end of the resolution spectrum in the way they look and the way they are styled. 512 x 512. This is still a treasure for people who work on lower resolution games, prototypes, crossplattform and mobile games as well as shaders.
Here is an impression of what is in the archive:
Shoutout to all fellow 3D artists. If you know of old resources and tools, archive them on a HDD somewhere, they will not be online forever and I deeply dislike this trend of streamlining every workflow to cater to the same handful of modeling and art packages. I think we will lose a lot of different looks and styles this way.
Anyway, I hope this will be helpful to some and keep creating!