Art, trash - opinions differ on this question. I think the beauty is in the eye of the beholder. In my point of view most generative art results are beautiful and partly even gorgeous.
Well, I´ve written this little snippet which has a few presets and rules so that the program allows you to switch between various painting-, form- and drawing-modes.
Btw., the sources of this example are part of an article I´ve written on Create or die.