I also use Tmobile with a Blackberry Curve 9300. Have used http://tether.com/ for years now. You can download a trial with your BB store or from the site. It goes on sale often, so don't pay the full price which is still a fair price. Its a small app that you start on you phone, bluetooth or via USB and a small app on you laptop. Works very fast, can stream video from skype on the fly in my car. Battery on the phone never drains because it's plugged into you computer, always charging. The nice thing is you don't pay anything to Tmoble for doing this. So the cost of the software is all you pay ever. Good Luck
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