You can drive in my city anytime......but do so at your own risk. I suspect cell phones come in handy when you lose control of your car while talking or even text messaging while driving and cause a wreck. In fact, I'd suggest a new feature be added to cell phones that would detect when the user is in an accident and automatically call 911. 
(This is from a transcript. Scroll down a little over half way past (COMMERCIAL BREAK) to PHILLIPS, then to SUSAN LISOVICZ, CNN CORRESPONDENT.}
You may have seen T-Mobile WiFi hotspots in places like airports and cafes. Now T-Mobile is offering a hotspot, which is a wireless Internet connection, for your home. The service comes with a phone capable of making calls wherever WiFi is available. ??With the service, any call that begins in a hotspot is free, even if you later walk around and switch to cellar service.
http://transcripts.cnn.com/TRANSCRIPTS/0706/27/cnr.04.html
I don't even have a cell phone.
What I've been able to gather is that text messaging is what can really drive up the bill. it doesn't say if that capability is included in the offering.
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