The most common gadgets in your home can be lifesavers in case of an emergency. 
Paper Bag -- Inhaling and exhaling 10 times while holding it over your nose and mouth can stop a panic attack.
Juice Glass -- To easily remove an insect from someone's ear, pour a glass full of warm water into it. The bug should float to the surface.
Milk -- If you knock out a tooth, put it in a container of milk until you can get to your dentist. The milk is a neutral solution that will keep the tooth from drying out, increasing the odds that it can be reinserted.
Yellow Pages and a Mop -- Touching someone who's been electrocuted can give you a severe shock. To insulate yourself, stand on a phone book, then move the electrical wire away from the victim with a wooden mop handle.
Bed sheet -- An adult suffering from heatstroke should be wrapped in a sheet soaked in cold water.
Pantyhose -- To support a broken collarbone, wrap a pair of pantyhose around the person's neck. Tie loosely in a figure 8 at chest level and place the person's hand in the bottom loop.
Credit Card -- When a bee or wasp stings you, gently use a credit card to scrape the stinger out of the wound, then put ice on the area to reduce swelling.