Not me but my mom and sister and me as the kid. I might have been around 6 when my older sis started to teach me some words and gestures not appropriate for my age. My mom obviously got concerned and brought this up with the two of us. "You shouldn't show your middle finger if you don't even know what it means. " - she said. "But I know what it means!" - I responded eagerly. "Oh really? Then tell me." "Fuck off." - I said 100% seriously. I'm polish so the exact word I said was "wypierdalaj" which cracks me up even more every time I think about it. The memory is pretty blurry to me at this point but the absolute shock on my mom's face and my sister wheezing with laughter was definitely something.