The curved shape of this stone reminded me of an IBM Selectric typewriter I used years ago. This small stone had an angled, flat front which was a perfect surface for painting typewriter keys. I painted a manual typewriter because the features seemed more charming and recognizable than the Selectric's.
The shape of this angular rock said "adding machine" even before it was painted. The numerical display panel features the year I painted this office machine.
This large, rounded stone was perfect for a car. Can you see the tire on the front, lower left of the unpainted stone?
As you can see, more than critters and flowers can be painted on rocks and stones.