Activation bypass methods (no sim unlock)
MAC: iNdependence (the new iActivator)
iNdependence is a Cocoa-based application for Mac OS X which provides an easy-to-use interface for jailbreak, activation, SSH installation, and ringtone/wallpaper/application installation on your iPhone. It’s open source under the GNU v2 license.
WIN: “Draken’s way”
Since there’s no working one-click-activation program for Windows yet user Draken from the hackint0sh forums wrote great two step guide for Windows users, which will take you from a brand new Iphone to a fully activated Iphone without hassle! Sim-unlock methods (don’t forget to show off afterwards!)
MAC/WIN: The SuperSIM method
With this method you change some things on your own providers SIM card to fool the iPhone, it’ll think that you inserted the AT&T SIM card. The method is a little bit expensive because you have to buy a SIM card reader/writer and a supersim, though with this method you don’t have to unscrew screws and “can’t” destroy the phone (note: this only works on “old” V1 simcards).
MAC/WIN: The TurboSIM method
You can’t fool the iPod by writing AT&T on your SIM card, though you can with this method (since the turbosim is sold out this can get a little expensive…).
MAC/WIN: The Hypersim / PSS SIM Kit method
This method is similar to the TurboSIM one, though hyper cards are easier to get and way easier to program (thanks to PSLiNK for the tip)
MAC/WIN: Hardware unlock
Difficult and dangerous, you can end up with an exploding iPod (ow, yeah, before trying this, read the disclaimer).
MAC/WIN: Software Unlock
Jailbreak the iPhone, bypass the activation, install this program and unlock the iPhone! Confirmed working by engadget and gizmodo, though it costs 100$ and you have to give them your IMEI...