This deal has ended.
Walmart.com has rolled back prices from $50-$75 and has this Canopy Hypoallergenic 8" Memory Foam Theratouch Mattress for as little as $150 for twin, $195 for queen or $225 for king. Shipping for twin adds $14.97 but all other sizes ship for $0.97. Free "site-to-store" shipping is also available. The Theratouch goes directly on a box spring and consists of two layers of foam.