This might have been covered before, but has anyone tried to use the Polycryo Ground Cloths from gossamergear.com for uses other then a ground cloth. the large size uses a precision cast polyvinylchloride that weighs .9 oz/sq yard. the small size uses a polyolefin film that weighs .55 oz/sq yard. has anyone tried to make a tarp or backpack or something out of this stuff? I've used the large size for a ground sheet and i was impressed by the durability and strength, i didnt try to sew with it, because i ended up loosing it :(. the only reason i can see this stuff failing is when you puncture it, it tears easier being that there is no ripstop pattern or anything. but i found it was pretty hard to puncture. anyway its certainly cheap enough, but i was woundering if anyone could save me some time and money, and just saying how horrible of an idea it is.