The Summerlite vanishes into a stuffsack too puny to accommodate a few hoagies I've eaten. Yet it's not claustrophobic like some ultralights. Designers achieved the feat by stuffing a gossamer 20-denier nylon shell with 850-fill down and paring back everything elseexcept warmth. It proved itself a choice summer-plus bag on near-freezing nights in the Puget Sound lowlands. 32°F, 1.2 lbs; www.westernmountaineering.comBonus: A full-length zipunheard of on a bag this light.Bummer: The hood drawcord hangs in your face when cinched.