This deal has ended.
The Serta 8" Full Size Memory Foam Mattress drops from $299.99 to $265.49 at Overstock. With free shipping, that matches the best deal we've seen on it to date. This same mattress is $399.99 at Amazon! It comes complete with a removable jacquard "eco-friendly" cover, and is well reviewed with 4.7 out of 5 stars from over 550 buyers. There's no sales tax (except UT).