This is an IMPORTANT reminder.
The blind print exchange is international in it's framework. It's one of the reasons so many choose to sign up. So, that said, when you do get a recipient that is outside your country, please do NOT state the value of photograph greater than $10USD / EUR 10 / equivalent or thereabouts.
Now, I realize that may be a blow to some egos, but otherwise, your print may languish in some customs office for months. And further, it may cause the recipient to pay a duty to receive the print, which he/she may or may not want to do.