BedinABox takes $100 off its mattresses via coupon code "CD100". Plus, Queen, King, and California King mattresses also include a free blanket. Even better, all orders receive free shipping. A couple of best bets, with prices after coupons:
BedInABox PacBed Original Memory Foam Queen Mattress for $779 (low by $70)
BedInABox Tranquillium Memory Foam Queen Mattress for $1,199 ($100 off)
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