A note to hikers: I hear there's a gallon of water in every almond, which makes them the most efficient source of hydration you can carry. Here's another great way to conserve water and reduce your carbon footprint. It can take 2,000 gallons of water to grow enough cotton for one pair of jeans. Then factor in the petroleum used to power the planting and harvesting, the transport and manufacture of each bale. What if there was some way to more directly convert crude oil into wearable raiment? What if a polyester doubleknit leisure suit is your greenest garment option?