Our thifty choice is to use our old shower curtain. Yes, we save our shower curtains when they are to old and beat up to be used in the bathroom. We wash them in the washing machine to get them clean. Because they are old, they do not have that gassy, icky smell. As for the krinkling, well, I guess we'll just have to deal. Your idea of a wool blanket sounds pretty feasable. I guess I would still want something waterproof underneath it as mattresses are such an important investment.
Kim. My heart is full! Wife to Ray, Mama to 3 boys! "Big C", our boy with designer genes, "Little C", and "Baby M" 11/2010.