Once the friend of a friend of my mom's was visiting Rio and she saw Sugarloaf Mountain and she wanted to impress her taxi driver with her knowledge of Portuguese, so she said in Portuguese "Look, Sugarloaf [Mountain]! It's very big!".
Unfortunately, English native speakers have a hard time making the "ão" sound correctly since the sound doesn't exist in English, so instead of saying "pão de açúcar" (literally, bread of sugar), she said "pau de açúcar." Now, "pau" technically just means "wood," but it's also, unfortunately for her, slang for "penis."
So to the driver what he heard was "Look at the sugar dick! it's so big!" and he almost crashed the car from laughing so hard.
