When I set up a shelter for the night, I always try to fill up two, 3 L platypus hydration bladders with water before I start cooking dinner: one for camp and one for the next day, so I can get an early start. However, depending on the distance between my tent, tarp, hammock, or a shelter, and the water source, it can be a real pain to carry to two, cold, slippery, 6 lb hydration bladders back to my camp.
So on my last AT section hike in New Hampshire, I used a trick I picked up from Jason Klass: a platypus hang loop. Simply thread some Kelty Triptease or heavier cord through the holes in the bottom of your platypus bladder. If you haven’t yet punched these out, just use a pen or other sharp object to perforate them. Some backpacks, like my old REI UL 60 have hooks in them or little dowels that fit through these holes and keep the bladder upright in a hydration pocket, which can be handy since it collapses on itself as it starts to empty.
Now, when you’re walking, or as is often the case, climbing back to camp, you can just sling the loops over your shoulder,making it much easier to carry the bladders and your filter, etc. Yet another reason why you should use platypus bladders, imho.