I've never been great at freehand drawing, so I quickly fell in love with generating art with code. The Lorenz Attractor was an early chaos algorithm I played with to do some of this code-generated art.
I've since created a tool in Processing that allows you to manipulate the variables and general algorithm at runtime and then output a vector PDF that you can bring into Illustrator or PhotoShop. These few prints are the results.
The tool itself is open source, and available for download here.