How can you test if an egg is rotten?
Good answer, 42girl. The reason rotten eggs float, of course, is because the bacteria that makes them nasty, funky and sick-making produces gas that collects inside the shell.
My method is easier, faster, requires no water and has a vengeance factor that appeals to those of us who hold grudges and have little in the way of a conscience: hurl the egg at someone you don’t like. If they get mad, it’s fine; if they retch, it’s a good thing you cracked it on his/her head instead of the side of a frying pan.