If you are afraid of jailbreaking your new iPhone 4 for fear of voiding your warranty and you have an old iPhone 3G or 3GS lying around that you are willing to jailbreak, you can follow these instructions to use FaceTime over 3G. What I used: iPhone 4 with data plan Jailbroken iPhone 3G 2 standard SIMs MyWi app 1. I traced the MicroSIM from my iPhone 4 onto a standard SIM and cut it out so the MicroSIM fit into the standard SIM. Basically, this was a cheap MicroSIM to SIM adapter. I made sure to cut so the pins would line up. I had to use a piece of scotch tape to hold the MicroSIM in place. To test, I put it into my 3G and it connected to the 3G network. 2. I cut the other standard SIM so that it would fit into my iPhone 4's MicroSIM tray. This is just a dummy SIM. Again, I made sure I cut so the pins lined up. I'm not sure if it makes a difference, but this SIM was from my old iPhone 3G. To test, I put this in my iPhone 4 and made sure the "No SIM" message went away. It was replaced with "No Service". 3. On the jailbroken iPhone 3G, I launched the MyWi app and created a wifi hotspot to which I connected my iPhone 4. 4. That's it! My wife intitiated a FaceTime call and it worked! The only stipulation is it has to be a FaceTime call. When my wife called my number, it rang on my 3G. It has to be a FaceTime call from the start and it will go to the iPhone 4. I tested this out and it works great.