Echo Store via Amazon offers Prime members the Slicoo Soft Touch Case and Keyboard Cover for Macbook 13.3" w/ Retina in four colors for $10.99. Coupon code "7NWWMC5Z" cuts it to $7.99. With free shipping, that's $5 under the lowest total price we could find for similar protectors elsewhere. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $6.52.) It's made of plastic covered in rubber.