None, yet. But that's only because I'm still figuring out wallet security and such. I've been into bitcoin for only about a month now, and it took me half that time just to figure out how to get any of the suckers. Eventually I decided on bitcoin2cash, which worked fine, but took a while. And I was pretty squeamish about sending money through USPS.
I'm not very technically proficient; I am just persistent. But if bitcoin is to obtain mass appeal people really need to figure out a cleaner and easier way of getting and using them.
Anyway, I'm thinking of buying a bitcoin shirt. If anyone thinks they can impress me with their design, show me.
I'm sure he'll tell you about it, but Gabriel Beal has some cool shirts on squarewear.biz.