upvoted it (at this time, it cancelled out a downvote). No idea why it was initially downvoted, it's good information to point out. So long as you don't make m

upvoted it (at this time, it cancelled out a downvote). No idea why it was initially downvoted, it's good information to point out. So long as you don't make money off the shirts, it's ok to use xkcd comics.