As one of its daily deals, Woot via Amazon discounts the PuraSleep 2" Carbon Comfort Memory Foam Mattress Topper in the sizes listed below. Plus, all orders bag free shipping. The deals, ending today:

• Twin for $69.99 (low by $43)
• Full for $89.99 (low by $41)
• Queen for $99.99 (low by $50)
• King for $114.99 (low by $50)
• Cal. King for $119.99 (low by $45)

Of note, it's also available in a 3" thickness, with deals starting from $84.99.