Um... what? Okay, is the joke supposed to be they got it from spam e-mail? I mean, it can't be something THAT stupid, or you wouldn't be buying a shirt for it. So, what am I missing here?
"On two occasions, I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able to rightly apprehend the kind of confusion of ideas that could provoke such a question." ~ Charles Babbage (1791-1871)
The person got an email that said something about Boron Cowpunch. The person who received it had no idea what it was, but they thought it sounded cool, so they made a line of shirts based on those two words.