If you have a bottle of champagne that has recently gone flat, drop a raisin in it. The carbon dioxide left in the bottle will cling to all the grooves in the raisin and release back into the liquid, making it bubbly again. (, , )

You can’t usually smell your own house (or perfume) because of a survival instinct called ‘olfactory adaptation.’ The brain is always looking for new, unusual, or changing smells as a sign of possible danger, so it ignores smells that have become familiar. (, )