I have had a iPhone 3G 2.2.1 sitting in a draw for a while. I wasn’t able to unlock it because the baseband was newer than required for using yellowsn0w, but with the release of 3.0 I have been able to unlock my iPhone using redsn0w and ultrasn0w. You use redsn0w to unlock the iPhone and install Cydia. And then you can use Cydia to install ultrasn0w. The ultrasn0w application then unlocks the phone so that it can be used on other GSM networks. I am frustrated that 3.0.1 has been released already, which is an obvious attempt to stop the hackers from unlocking phones. But I am sure that before not too long that an update to ultrasnow will be released. In the mean time I have an unlocked iPhone 3G. :)
