If you've got an iPhone & are looking to use a carrier other than AT&T, the guys at TweakTown have posted a guide to help you do just that; using a modded SIM card.

"The third which surfaced recently is similar to what we are going to show here but a little different – it involved modding your SIM with a special module adapter but we are unsure of all the details on the procedure of that mod... until now."