Some expensive calls. I've got the unlimited long distance package for $20/mo through Qwest so doesn't matter how many calls I make, it's still about $20. Never have any reasons to make international calls...so that's not an issue.
Cell phone bills can add up quick though if you go over or have roaming charges...
Back in the early 80's I had an Importing Company
(Rattan furniture & Batik clothing) from Bali/Aus to the U.S..
$6,000 a month wasnt unheard of, and $3-4,000 pretty regular.
It was all a bottom line write off though.