I've started using my 3/4 length (cut down) Wal-mart sleeping pad as a windscreen for my alcohol stove. I was experience a tremendous drop in efficiency when there was even the slightest breeze despite my use of an aluminum windscreen.
Since the Wal-mart pad is stiff enough to be free standing, I tried using it as my windscreen. Even when I fully surround my stove with it, there's almost six inches of space between it and the pot. I've cooked with it a couple of times, but I don't have an apples to apples comparison yet. I can definitely say that it works as well as the aluminum screen so I can get rid of a couple of ounces by using the pad. If it improves efficiency (because it's an insulator) so much the better.
