Turbo SIM – iPhone 1.1.2 unlocker
December 27th, 2007 
If you have your iPhone 1.1.2 locked, then the simplest way to unlock it is by using the Turbo SIM. It is very easy, just prepare yourself your SIM card, the turbo SIM and a pen knife. After that, cut your SIM card according to the turbo SIM IC chip. Then, place your SIM card together with turbo SIM and put in to your iPhone. Finally, your iPhone is unlocked. Get a Turbo SIM for $79.
this post is very good.
2008 New iphone unlock introduction:
1. Turbo sim with 3G Sim card support
2. Turbo sim with STK function support
3. The version is developed by Taiwan Star Telecom , as the Magicsim 21th latest generation
Description:
● It works on latest OTB (out of the box) 1.1.2 iPhones (week 45 or newer)
● The TurboSIM Chip basically fools the iPhone think it is using AT&T SIM card.
● Turbosim is very thin piece of film circuit that goes between your real sim card and the phone sim socket.
● It is hardware unlock , no damage on iPhones baseband firmware and hardware.
● Your SIM card will still work on ordinary phones without Turbo sim. Just a few simple step to free your iPhone for Any GSM Network.
● To unlocked your locked iphone version 1.1.2 .
● Use this turbo sim with your sim card to get your locked iphone version 1.1.2 unlocked.Now you can use any sim cards in iphone .
The best turbosim for iphone unlock
http://www.magicsim.com/en/cp_show.asp?id=43&cp_id=35&sort2name=12