So I'm pretty sure that I know the answer, but before I put down a few hundred dollars for a used iphone, I had a question. If I currently have cingular and want to use the iphone without paying anything more monthly, I could do that by using the pwnage tool to unlock it and then turning off the GSM/EDGE networking, right? Everywhere I usually am is within a wireless network so I don't really see the need to pay extra for the GSM. Is it possible to turn off GSM so that it would only connect to wireless networks? Just so I know what I'm getting into, besides just internet browsing, what else relies on the GSM network? I presume the "GPS" like feature on either type of iPhone would need it. I can't think of too much else though. What do you all think? Would turning an iphone into a ipod touch + regular phone at the same monthly cingular price be a wise move?