Almost everything I do starts with code, as almost all of my artwork is generated by software. In these cases the resulting animation, sound or image is the goal, not the program that created it.
In other cases I aim for the software itself which demands a much more careful design. I put my source code up on GitHub and most of my software is open source. I also started submitting patches to open source projects I use, as it’s a very good exercise and I can get rid of the bugs that bother me.