This may seem stupid but I'm packing and can't think straight. I'm going to South Africa for a week. AT&T international roaming fees for voice and data are ridiculous and I don't really care to use them. I would like to jump on any open wireless networks that I find -- without the phone looking for a cell provider (EDGE is actually available in some places...) I ONLY want to use open WiFi spots and the iPod parts of the phone. Since my phone is registered and all, can I just take out the SIM card and use the iPod and WiFi functionality? I don't want to be stuck with a huge data bill so I'm hoping that method keeps them from charging me. Es posible?