This deal has ended.
The Apple Store now has Apple Certified Refurbished MacBook Airs starting at $749 for an 11", 64GB, i5 model. Plus, you can upgrade to the recently-released Mountain Lion OS free! Mac refurbs have an excellent reputation, and they carry the same 1-year warranty as new Macs (extendable to 3 years if you purchase AppleCare). Ground shipping is free. Sales tax is charged in most states.