Tethering a smartphone to your laptop and using it as a wireless modem to access a network operator's 3G data network seems like it should be a slam dunk. Even though the iPhone can access AT&T's 3G goodness, AT&T won't permit it to serve a modem.Tethering is something that should be available for any 3G device. Alas, it isn't. At the moment, I have a separate account for my phone, and another for my 3G wireless data modem. Since 3G phones can access the same network, why not eliminate the middleman and allow it to serve as my wireless modem instead of necessitating two accounts? Several reasons are playing a role here.

First and foremost, revenue. My network operator would rather I have two accounts and give it more money each month. Even though I'd be glad to pay a small premium for the data access charges on my phone to use it as a modem, it's not an option for me right now. I would expect to be able to save between $30 and $40 per month if I could combine both my standard wireless phone charges with my wireless data modem charges.

The bigger reason preventing AT&T from allowing 3G iPhone users to tether them to laptops likely has to do with network capacity. If every iPhone user started attaching their devices to their laptops and browsing the full Internet and downloading files, it could strain the network.

Right now, 3G iPhone consumers will have to pay $30 per month to get an unlimited data plan ($45 for a business account that accesses either BlackBerry's BES or Microsoft's Exchange servers). If AT&T bumped that amount by $10 or $20 per month, and allowed tethered browsing, I'd be happy. That doesn't appear to be in the cards just yet, however.

According to iPhoneAtlas, which broke the news late last week, hackers of the first-generation iPhone were able to enable tethered browsing (though why you'd want to over EDGE doesn't make much sense). It is possible that the 3G iPhone will be hacked, but who knows if/when that day will come.