We all know that collapsible water bladders are a light, compact solution for on-the-move hydration. But don't limit these multitasking tools to mere drinking duty. New and recycled reservoirs have many uses beyond thirst-busting. You can use yours as a:
Shower: Fill it with warm water, screw on a push-pull lid, wet yourself, close the nozzle, soap up, then rinse off.
Urinal: On winter camping trips, guys will appreciate a .5-liter bottle for wee-hour relief. Wide-mouth reservoirs reduce the risk of annoying spillage.
Pillow: Fill it with air or water, and wrap it in a shirt.
Hot-water bottle: Fill a bladder with steaming water, tuck it next to your belly, and sleep comfortably under the stars.
Air conditioner: In the summer, add snow from late-melting drifts to your wide-mouth or zipper-lock reservoir, then tuck it against your back to keep cool. On sweaty winter hikes, refill your bladder with snow after each drink. Place it under your shirt--you'll sweat less and convert snow into drinking water.
Folding bowl: When your bladder wears out, cut off the upper two-thirds and use the bottom to hold breakfast and dinner.
Flask: There's no lighter way to tote a little wine or schnapps.
Waterproof storage: Zip or roll-top bladders can shelter maps, binoculars, and small cameras.
Cold pack: Speed the healing of strains, sprains, and bruises by applying a snow-and-water-filled bottle to the injured area.
Deadman: Fill a wide-mouth or zipper-lock bladder with snow, tie a guyline to the handle, then sink it deep in a drift to hold down your tent.
Among the most versatile bladders are Nalgene's 1.5-liter wide-mouth canteens ($11), Platypus's Big Zip 2 2-liter models ($23), MSR's DromLite 2-liter bladders ($18), and Camelbak's 2-liter UnBottles ($30).