The Prada of battlewear has come up with a super-packable alternative to your trusty-but-bulky fleece. The Atom uses a light, lofty insulation called “coreloft” to keep you warm during stop-and-go activity in cool to cold weather. What’s really cool is the huge, breathable powerstretch side panels that lets your stink out when your internal furnace is pumping.

The mid-layer weighs in at a measly 10.6 ounces and repels a light rain and deflects more wind than a wind-stopper fleece. Other features include a luxurious brushed collar, a longer cut, insulated zipper flap, an internal pocket, an athletic cut and longer sleeves that will allow you to shoot prone without exposing your wrists to the chill — or the enemy. Available for $160 in fall ’09. Arcteryx