I downloaded all 2D art of OpenGameArt, unpacked the archives and extracted the sprites, then recompiled it as 3 huge 32x32 image, with images grouped by similarity. It is intended to be browsed only to get a sense of what exists on OpenGameArt. The images are too big to upload here, total almost 1 GiB, so I host them on my own server at
https:̸ ̸ emh.lart.no̸ publish̸ opengameart̸ and upload a preview here (also at https://opengameart.org/content/all-of-opengameart-in-3-sprite-sheets). The files were downloaded in November 2019.

The license list can be found at https://emh.lart.no/publish/opengameart/license.html .

Source code for generating the images can be found at https://github.com/emnh/opengameart/.

Let me know what you think (if you have the bandwidth to download, and decent computer to watch the images, hehe. but also otherwise, of course :) ! :)