I was shopping at a local Joann's the other day and encountered several rolls of nylon fabric that was not the stuff found in their 'utility fabric section'. It wasn't the heavy 'sport' nylon, or ripstop. For the life of me, I cannot remember the precise label they used, but it was 100% nylon, and labeled something similar to "Memory Jacketing Material". This could be way off, but Jacketing was definitely one of the terms.
What is this stuff, exactly? It seems to me to just be a lighter weight, more pliable nylon, maybe intended for garments? I haven't had any luck with Google so far. The prices on it were still rather high, $6/yard, but I did pick up a couple yards just to tinker with.
I also stumbled on some 'weather resistant' fabric that was polyurethane backed polyester. It had a thin, very flexible rubber layer on the back of it. It seems like this stuff might be a challenge to waterproof at the seams, but the biggest reason I didn't buy the whole roll at $4/yd was I was suspicious as to how well it would stand up to UV. Something in the back of my head was telling me that polyurethane layer was going to get brittle when exposed to sunlight. Anybody able to comment on this stuff as a tarp or ground cloth material?