This is a really neat boat: a kayak made from willow and poly tarp: http://www.shelter-systems.com/kayak.html
I am thinking one might be able to make this or a coracle with withes (other than willow) a tarp and some cable ties which I could leave in a drum at one of my hunting camps upriver so that I could float down stream if I wanted/needed to.
PS: They also have these really excellent tarp clips: http://www.theultralighthiker.com/best-tarp-clips-link/
