Leaving aside the file format discussion for a moment, I think Freedom
Box t-shirts would be great for raising a small amount of money *and*
building awareness for the project. Inexpensive matching stickers
would be nice, too.
On the timing issue, it seems like there are loads of conferences
where people might want to buy shirts happening between February and
October 2013. Perhaps the next step in this process would be to obtain
pricing so we could decide if the outlay was worth it?
Thanks for bringing it up, Alexander!