I always used to crack eggs one by one into a cup before adding to anything, (habit instilled in me by my mother who would also sniff each egg before tipping it from the cup into the mixing bowl), but had never had a bad egg so started just cracking them directly into the bowl. However... just cracked one into my cake mixture, and the smell!!! So disgusting! Luckily only making 12 cupcakes and it was the first egg added, so not too much to throw away.
I'll be going back to my old ways again after that experience!
It must be pretty rare these days with supermarket eggs - anyone else had a bad egg?