Need to haul something? Is it odd shaped or a little messy? Sounds like a great job for a bucket! But who brings a bucket on a hiking or camping trip? We thought the same thing before we came up with a portable one, and being made of canvas, it's collapsable.
Handcrafted in 18oz waxed canvas, it will hold approx. 3.75L. Yes, they'll leak a little (what do you expect from a canvas bucket?). We left one filled overnight, in the morning there was still more inside than what leaked outside. That's certainly long enough to get a load from a stream and back up to camp.