[quote author=mastertangler
What might be slick is a "hanger system" where one avoids having to employ a limb in the first place. It would have to be quick, easy and weightless and be able to stash itself in the stuff sack the platypus resides in. Just a thought. No more looking for the right branch.............Just slap it around a trunk with its little arm and it is always the right height with no bark falling in.[/quote]

Funny you should mention that.  My system is simple and lightweight and does just what you suggest.  I wrap a 1/2" rope around a tree about 6-7 feet high, with a loop in the end hanging down a few feet.  I clip a double-ended snap shackle to the rope and another one to the loop.  Each one holds a water bag.  It's easy to switch the bags, and the hose doesn't touch the ground.

I also use a 3-gallon reservoir with a third hook, but it would be too complicated to describe the entire setup.