These are instructions on how to activate your iPhone 3G, 3GS, or 4 without having the original SIM or being on the original network.
****Apple has blocked this as of October 29th, 2010****
This is more of a tip then a tutorial. Sherif Morano has discovered that iTunes will activate your iPhone if a PhoneBook SIM card is inserted. A PhoneBook SIM card is used to transfer your contacts from one phone to another. They can be purchased from Radioshack, Mobile Phone Shops, or online.
You might want to use this card if you need to activate before applying a jailbreak then unlock.
Congratulations to Sherif for this discovery. You can watch his video demonstration below...