Thanks everyone for these comments. We received so many negative comments so it is especially sweet to hear positive feedback!

In response to Marianne and to parwatisingari, I wanted to mention a few quick things. Marianne, there is a really rich tradition of documentary films set in public toilets. One of the things we do in our introduction is try to cite as many as we could find. I've noticed that our publishers have made our intro available as a PDF which can be freely downloaded from their website: http://www.temple.edu/tempress/titles/1992_reg.html So you can check out the list. There are many that I really like (and I am currently writing about Peter Greenaway's amazing 26 Bathrooms), but one of most outstanding is about public toilets in India, Paromita Vohra's Q2P, 2006. Everyone should see this film! At one point, I know this could be downloaded from the web, but I can't find the link now. However, it is relatively easy to get a hold of and well worth the effort.