At my workplace, there's a mysterious carton of eggs in the common refrigerator. Nobody I've asked knows whether they're raw or cooked.
Is there a way to tell, without cracking one of the eggs open?
Take an egg from the carton and 'spin' it on the work counter. If it spins, it's cooked, if it does anything else, it's not.
Shake the egg like you would a rattle. If the insides move, raw. If the egg feels solid, cooked.
The spinning trick is good, but instead of just spinning and then stopping, if you spin it in one direction, stop and try the other direction, a raw egg will spin badly in the opposite direction. The reason is of course the liquid is still going the other way.