WAIT!
so you're telling me that i can browse the internet for FREE on my cell phone?!
Do you have a data plan? It will work if you don't have a data plan but you will be paying per kilobyte used. If you have an unlimited data plan you can browse as much as you want. Using Opera Mini is free but to use the data service through your carrier isn't.
Do you have a Data Plan from AT&T? it's $29.99/mo. If you have that - then no, no additional monthly charge. If you don't have the data plan, then you will be charged per KB of data used on your BB.