Screen Printing
One of my hobbies is screen printing. I have a small 4 color press set up in my studio (read: garage), and I really enjoy the process of creating a design through actually generating a physical artifact. I apply this to my software design process - it's just pictures unless you build it.
This is my set up for a three-color shirt.
This is a sample catalog. I've printed and sold or gifted a lot of these.
