Hot or not, Costco has the Novaform Matress Toppers on coupon. I bought one at a BM, plenty there. Comes with a cover.
Also on-line This is Costco.Com [costco.com]

Valid for orders placed January 24, 2005 through January 30, 2005 - Same in Store.

Queen Mattress Topper #812226
Online price $111.79
*Less coupon -$30.00
YOUR COST $81.79

King Mattress Topper #812227
Online price $134.99
*Less coupon -$30.00
YOUR COST $104.99

Cal-King Mattress Topper #812228
Online price $133.99
*Less coupon -$30.00
YOUR COST $103.99

Full Mattress Topper #812225
Online price $99.99
*Less coupon -$20.00
YOUR COST $79.99

Twin Mattress Topper #812224
Online price $89.89
*Less coupon -$20.00
YOUR COST $69.89

Developed for NASA to provide relief for astronauts undergoing G-forces, this revolutionary "Memory" foam mattress topper immediately responds to your body's heat and molds around you, relieving pressure points and improving circulation. With exceptional therapeutic cushioning and support, you will enjoy a peaceful night's sleep and wake up feeling refreshed and rested.

Sizes: Cal-king, king, queen, full, twin
New 2.5" thickness for maximum comfort and support
75% cotton / 25% white polyester terry velour cover/washable
High density foam is 4 pounds per cubic foot, made with 100% visco elastic polyurethane foam
Customized comfort: Temperature sensitive "memory" foam molds to your body; returns to original shape after use
Non-allergenic: Ultra-Fresh™ antibacterial agent added to foam
Healthful: Relieves pressure points and improves circulation
Leaves you feeling refreshed and rested
Twin dimensions:
39" x 75" x 2.5"
Full dimensions:
54" x 75" x 2.5"
Queen dimensions:
60" x 80" x 2.5"
King dimensions:
76" x 80" x 2.5"
Cal-king dimensions:
72" x 84" x 2.5"
Made in the U.S.A.