For example here the one from Gimp:
Changing this image is something really very simple, it is found in /usr/share/gimp/2.0/images/ under the name of gimp-splash.png, we just have to replace that image with the one we want and that's it, it's that simple. I already explained this in detail in the post: How to change the splash or startup image of Gimp
In fact, in that previous article I left you 3 other splashes for Gimp, well here I leave a tablet that has almost 30 splashes for Gimp:
To download the tablet with all these and some more here I leave the link:
When they download and unzip it, the procedure to put one is very simple, for example suppose they want to put the first one whose name is 112949-gimp-splash.png, the commands would be:
sudo cp 30_gimp_splash/112949-gimp-splash.png /usr/share/gimp/2.0/images/gimp-splash.png
And voila, it would look like this:
Well nothing, the post ends here. I hope it will be you useful.