Sam's Club offers its members the Serta Ultra Luxury Hybrid Shoreway Plush Mattress King Set with 5.75" or 9" boxspring for $999 with free white glove delivery. (Delivery includes basic set-up and haul-away. Non-members pay an additional $99.90, so it's better to buy a 1-Year Membership bundled with a $10 Sam's Club Gift Card for $30.) That's $600 off and the best deal we could find. This smooth-top mattress features a 14.75" profile and hybrid gel memory foam / individually-wrapped coil design. It's compatible with Serta adjustable foundations (sold separately).

It's also available in Queen for $699 with free shipping. (As above, non-members should purchase a 1-Year Membership bundled with a $10 Sam's Club Gift Card for $30 to avoid the $69.90 surcharge.) That's also $600 off and the lowest price we could find. Both deals end October 15.