I started with Sean's blessing, the APUG branded stuff nearly 2 years ago.
Subsequently I did some hoodies and long sleeve tees.
There was an initial good response, but overall, and after two years I still have stock left, though sizes are limited. When these run out I will not repeat the effort as the outlay of cash and time vs. the response was a bit disappointing.
But, wearing the shirts hopefully has created some awareness to APUG that otherwise would not have happened.
I wear mine alot, and have been asked several times "what is APUG?"