Can't you Hack or Jailbreak the iPhone?  

 If you're brave, you can always try to hack the iPhone in order to get prepaid service from AT&T. There are a few sites detailling how to hack the iPhone and then activiate a GoPhone service in order to work around the system. But in doing this you run the risk of decreased support, and possibly even violating your warantee. That is a risk many customers may not be willing to take.

So how does it work? Follow the link to find out...

AppleIphoneReview has some instructions:

• How to Jailbreak Your iPhone in Under a Minute 

 LifeHacker has an article about Jailbreak apps:

•  iPhone 2.0 Jailbreak Apps you can't find in the iTunes store

Tuaw has a series of articles about how to hack your iPhone to work with Prepaid:

• Part 1: Prepaid iPhone in a Nutshell
• Part 2: iPhone: Prepay the right way
• Part 3:iPhone + Disposable Cellphone + Prepaid Cards + New Activation Tool = Holy Cow

 Phonenews.com has a guide:

•  How To: Get an iPhone 3G for $199… Without Contract! (Updated)

Cellfanatic also has a guide:

• Iphone GoPhone Prepaid Service: Unlimited Text, Internet + 200 Minutes