Last year Apple offered a free iPod touch or iPod nano with a Mac purchase in their Back to school deals.
The Apple Back To School Deals are for student, teacher, or staff member only and usually are available from June to September. MacRumors reports that Apple might announce the Back to School deals already tomorrow. Apple is rumored to be offering the 8GB iPhone 3G along with the 8GB iPod touch and 8GB iPod nano for free with a qualifying Apple Mac purchase. Update: Apple Back To School Deals official.

Of course you still would have to sign a 2 year contract with AT&T, but you would save the $200.
Apple just recently started offering the iPhone 3G in their online store. Of course such a rebate promotion would help clear the inventory of the 8GB iPhone 3G and make room for the new iPhone 2009.