Personally I don't use and soap or shampoo, I just shower every morning. It's something that I don't usually like to admit, but my hair and skin has never been healthier. A old roommate told me about going without shampoo (takes about a month for your hair to get used to it), but it's been about four years since then and it still works great. The hot water is probably worse for the environment than the soap production, but it's a bit more sustainable.