Walmart offers the Better Homes and Gardens 12" Gel Infused Memory Foam Queen Mattress for $159.01 with free shipping. That's the lowest price we could find by $54. It features 3" of Theratouch gel memory foam, 3" of comfort foam, and 6" of high-density support foam.

Note: King is available for $199.01 with free shipping, for a low by $80.