We've all read the horror stories, so I try to be careful when going overseas. But my wife's (i)phone escaped my control last month when she went overseas before me.
iPhones hide the sim away a bit so she forgot to take hers out when she landed, she sent quite a few 80c txts, some by choice, some by certain apps inviting people via txt, but she was mostly using it as a wifi device.
What annoys me though is the call to a local (Brazil) number, that no longer exists, being charged $7 for a call that apparently lasted .01 minutes. When I tested it from a local landline it just sounded engaged.
At least the $30 p/mb data never kicked in, there is hope for her yet ;)
I know there are ways to avoid all this, but it is just so punishing, one misstep and you fall so deep!