I'm researching my options here. Option #1: Add an international data package (120 MB costs $30). Pros: Won't void warranty, is as easy as calling AT&T and is cheaper than paying AT&T's price/MB, depending on how much data is used. Cons: Pretty expensive and may risk losing unlimited data (which is a factor). Option #2: Go without a data package. Pros: Won't void warranty and will allow the service member to keep his or her unlimited data. Cons: Can be more expensive than option #1, depending on how much data is used Option #3: Unlock the phone so it works with a prepaid SIM card. Pros: Probably cheaper than options #1 & #2. Con: May void warranty, depending on whether the phone is unlocked via hacking software. Option #4: Avoid using the cellular connection and only use the Internet via WiFi.