Hallo!
I just had a look at the documentation of the pd-convention 2004 and
noticed that some people weared pullovers and t-shirts with a 'bang- message'-object printed at the front, seen here: http://puredata.info/community/projects/convention04/chronik/sonntag/ ankunft/
Unfortunately they where sold out very quickly ... (I also was too slow and only got a T-shirt ... :( I don't think that it is planned to build more from them ...
LG Georg