World's tiniest Egg!
I've had several eggs that small, and one that was just a tiny bit bigger than a dime once. They're pretty cool! :)
I'm the proud owner of a flock of wonderful chickens, ducks, and geese, 5 rabbits, 1 dog, 1 cockatiel, 1 betta, and 2 cats.
Check out my blog, if you're into that kind of thing: http://www.trainedbyahorse.blogspot.com.
"Everybody dies, but not everyone lives" ~Cross The Line, Superchick
That's not rare at all :) Young hens just starting out will lay "wind" or "fart" eggs - usually tiny things with no yolks. On the other end of the age spectrum, I just got two eggs smaller than yours from my very old hens. They're trying to lay, but not able to make a normal eggs. One looked like a speckled wild-bird's egg. Very cute.