Movie theatre bathrooms are a close second. I've had times when I really needed to go, and the restroom has been empty, and it goes a little something like this:
Toilet 1: Looks like somebody did a few yoga moves whilst pissing.
Toilet 2: Spontaneous abortion, complete with multiple used tampons.
Toilet 3: OMFG-I-can't-touch-the-seat-so-lets-pile-5
Toilet 4: Clean, with small spot of pee on the seat.
Me: I'LL TAKE IT!
Women are so gross