My poor baby tomatoes (I know, I'm sad) have blossom end rot. As this is the first time ever a tomato plant of mine has gotten to the fruit phase, I am probably more concerned about this than is strictly normal. I've done some research, and low calcium in the soil and dehydration can cause this, so apparently my plant is a post menopausal marathon runner. Or something.
My bananas are totally black too, but that just means banana bread. I love that old bananas work great for that because then forgetting them and letting them spoil ends up working in my favor.