If you're taking your iPhone on a trip, be sure to turn off automatic email checking. Jon Henshaw writes:
Stasia Holdren, our VP of Business Development and our Google AdWords guru, recently taught a one-day AdWords seminar in Vancouver, Canada. Although the city is relatively close to Seattle and is a larger metropolitan city, she was technically on an International roaming connection. She was mindful of that and only made calls from her phone when she had to. Unfortunately, her iPhone had other ideas. Since her phone was set to check email every few minutes, she was charged giant roaming fees for every new connection made, along with the time and data of each connection. She racked up a $600 bill from AT&T in just two days, and that was in Canada!