Free Software iPhone Unlock

This means AT&T is no longer the exclusive carrier for the iPhone. If you're in Europe or dying to use your iPhone on T-Mobile's American GSM network, this is good news. For a simple application that does all the the dirty-work, check out freeiphoneunlock.com

NOTE #1: Even though the program at the above link will do all the work for you, this is still very much hacker-territory--If something goes wrong, blame yourself.

NOTE #2: There is no reason to do this if you live in America and your iPhone is already on the AT&T network. (unless you'd like to travel to Europe and insert a different sim card to avoid ATT's crazy international roaming charges.