Just in case you don’t know about the corporate or education discount for your iPhone 3G paln. You can sign up for the discount following this link.
You need to have a valid business or school email address to do it.
While I was waiting on the line to purchase my iPhone, I heard that if you are a AAA member, you can get 17% off your plan. I called the AT&T store and they told me to bring my AAA member’s card to the store and they will link my number to the card.
Note that there is no discount on the phone itself and you cannot do this at the time of your purchase of the phone at the Apple store.
I signed on using the link and I just saw the discount when I logged on to my account. It shows the discount for me is only 10%. I guess it depends on the the agreement between the company/shool with AT&T. I have yet to link my AAA account to it. I’ll see if it’s better.