I heard this joke last week:
Okay, so there was this woman at the grocery store standing in the check out line with her groceries.
There was a bum standing in line behind her. He watched the woman put her things on the conveyor belt and made the statement: "You're single, huh."
She looked at what she had before her: a can of coffee, a gallon of milk, a half a dozen eggs, a stack of T.V. dinners, a box of cereal, a candy bar and pack of gum.
After looking at her groceries and trying to figure out how the bum knew that she was single, she was pretty impressed and confused. She turned and looked at the bum and said, "Excuse me, I can't figure it out, what gave it away that I am single?"
The bum said, "You're ugly."