Trying to decide whether or not to buy a 8GB IPhone that I could hack to use on the TMobile network, but I need some help. I have some questions...How can I unlock the phone? I know I have to run a hack program, but if I want to use on a TMobile network can I use an old TMobile phone SIM CARD? or will I have to find a new one that hasn't been used...also whats the cheapest way to go as far as plans/minutes/data plans/etc...any help would be awesome! Thanks