The game is written in Python and isn't very efficient. It is really satisfying tough.

Falling Sand is a satisfying sand simulator written in python with pygame. You can change the color of the sand and place it wehrever you want.

Tu run it, download the source code and run main.py

After running the game, you can place sand by clicking with your mouse at the desired spot. Press 1-7 to change color.

PS: I spend way to much time in this game :)