Swiss sculptor Jean Tinguely used to make machines that created abstract paintings. The machines themselves are quite nice to watch and work as art in themselves. Take a look.
I talked about De Stijl yesterday. Piet is a programming language whose programs can look like De Stijl paintings, although you can see from the samples that people have created all kinds of patterns, like the giant red circle that calculates an approximation of Pi, or the 'Hello World' that looks like the world.
Every issue of De Stijl Magazine in PDF form. I can't read Dutch, but the visuals are incredible.