Need a jacket capable of vanishing? The Patagonia Houdini Rock Jacket packs down so small it may as well have disappeared. Made from an ultra-lightweight full recycled nylon ripstop, it makes for a perfect wind barrier and is a great layer to have to hand for cycling or running on the trails. A one-pull adjustable hood which doesn't impinge on peripheral vision and half-elasticated cuffs round out this superlative bit of kit.