I'm a polycryo fan as well (I use the heavy duty window covering which someone else mentions). Because it blows away so easily, put small pieces of gorilla tape at each corner, then added grommets. I can stake down the polycryo so it doesn't blow away, and then set up my shelter. I can then remove the stakes from the polycryo if I wish. Works like a charm, and has lasted for a couple of backpacking seasons so far.