Another one of my favorite crafts is making custom t-shirts with my own designs. I'm not a famous graphic designer, yet, but I can pretend that I am when I wear a t-shirt with my own artwork on it.
The Beavis wearing one of my designs
If you haven't tried iron-on paper yet, I highly suggest it. Be sure to get the type of paper for the color of shirt you are going to apply it to. I like using the paper for dark shirts because I can create a white border around my images.
The print isn't as nice as a silk-screened design and will fade with washing but I like the faded effect.