[Figure1] Credit: The_Gut Source: <a href="http://www.flickr.com/photos/frogbelly/3851056758/">http://www.flickr.com/photos/frogbelly/3851056758/</a> License: CC BY-NC 3.0 Commercials for waterproofing sprays commonly show water and other water-based liquids, such as wine, mud, or chocolate sauce, being poured onto a treated surface.