There's nothing worse than cracking open a rotten egg, but it can sometimes be hard to tell if your eggs have gone bad just by looking at them. About.com shows us a simple trick for telling if an egg is bad, without having to open it up and see.
All you need to do is fill a bowl with cold water and place the egg inside. If it sinks to the bottom, it's good. If it sinks but stands on its point, it's good, but won't be good for much longer and should be used soon. If it floats, toss it. This works because old eggs will have lost a lot of the liquid on the inside, evaporating through their porous shell -- causing the egg to float instead of sink. Hit the link to read more.