Good point, loose rivets. I remember when making even a domestic long distance call, let alone an international, was a big deal and you did it with sweating palms and one eye on the second hand!
Roll on the years, I don't even think of the cost, it's such an insignificant portion of outgoings it's not worth a thought. In our household, 95% of our telephone traffic is international and we're talking several hours daily (which is better than having mother-in-law here!)