Smoke inhalation causes most fire-related deaths. Knowing that, William Holmes found out how to keep you conscious while you wait for rescue—as long as you can handle having toilet breath. In 1981, Holmes patented a snorkel-like device that supplies fresh air from your sewer. Just feed the tube past your throne’s water trap. Although you won’t die from a lungful of smoke, you might get woozy after huffing all that sewer gas.