Many years ago, I got a cheap screenprinting kit and my brother and I started playing around with making postcards and t-shirts.
These days, it's a full-blown hobby. I have a four-color silkscreen press in my studio (aka garage) and I design and print shirts and posters sometimes.
These are a few samples of some past designs. They are inspired mostly by the late 1960s and early 70s heyday of graphic t-shirts. Some are direct reprints of designs found in comic book ads. Others are public domain art from NASA. But mostly they are just things that either cracked me up or I thought would look awesome on a shirt.