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Apple.com has Apple Certified Refurbished MacBook Airs starting at $849 for an 11", 64GB, i5 model. Note that refurb stocks fluctuate. 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). The ultra-portable, ultra-thin MacBook Air has a solid state drive for improved performance and includes the iLife '11 suite of applications. Ground shipping is free. Those models that ship with Snow Leopard can upgrade to OS X Lion 10.7 for free. Sales tax is charged in most states.