Today in eco-friendly building: over the next four years, recycling company Knowaste will open five U.K. factories aimed at converting used diapers, incontinence, and feminine hygiene products into building products such as roof shingles, siding, and commercial tubing. The process works something like this: the disposed waste is sterilized and treated with chemicals, then the plastics are filtered, cleaned, and turned into small pellets. Et voilà! The underpinning of a new house is born. According to Knowaste, each new factory will process 36,000 tons of waste per year from childcare centers, nursing homes, and hospitals, and up to 98 percent of each used diaper can be repurposed. Squeamish? As Gizmodo commenter AnnexOne points out, "It's gotta be better than the foam and plywood that most modern houses are built with."