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Apple.com has Apple Certified Refurbished MacBook Airs starting at $699. Note that refurb stocks fluctuate and the lowest priced models will go very quickly. 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, and if you purchase a printer on the same invoice, there is a mail-in rebate for $100 off a printer. You can upgrade to OS X Lion 10.7 for free. Sales tax is charged in most states.