Once upon a time, the idea of sleeping on an air mattress during a night in the backcountry gave hikers the shivers. Why? The mattresses provided good cushion but zero insulation. Fortunately, the Therm-A-Rest NeoAir XLite is the lightest comfortable air mattress available. Multiple layers of crinkly reflective sheets within the mattress's core provides sleepers with warmth, while a cushy 2.5 inches of padding protects their hips and spine from the hard ground. The standard-size 72-inch mattress packs down to the size of a water bottle and weighs a mere 12 ounces. [$160; cascadedesigns.com]