When I was a kid, my sister found a big roll of pink stuff in our basement that looked like cotton candy and unknowingly ran her hand across it. She instantly became red and itchy: she'd come in contact with fiberglass insulation which my parents had been using in a remodel. The man-made mineral fiber can cause a range of health problems, including immediate skin irritation and respiratory troubles resulting from inhalation, if not worse. There are plenty of dangers of DIY, especially if you're using sharp objects, like saws or knives, or even fire. Last week you told me what your biggest DIY was, so now I want to know: what was your most dangerous DIY?