Tethering

[MoKuJoN]

Is it free to use?

[Youngbinks]

Yes and no. It's free in the sense that AT&T isn't currently charging for it but you must be careful. The "unlimited" data plan for the iPhone includes an understood cap of 5 GB per month. So if AT&T notices that you're using a considerably large amount of data, they might start asking questions. Just a heads up.

[ninjashoes]

Tethering is great

I actually got my ps3 online through tethering my phone to my comp, that was pretty cool