In all reality, the cell phones themselves could also be used as standalone two-way radios. That would help in remote areas that may not have adequate cell coverage. I'm not sure, but I think GSM is supposed to eventually eliminate that because of satellite coverage. But hey, wouldn't it be cool to be able to call your friends out in the middle of nowhere without a cell tower? Oh, you just broke your leg, all by yourself and calling for help for anyone to answer? You're dead. It's illegal to monitor cell phone transmissions (plus, they're digital), even for life threating emergencies!