Probably IABU, but this shocked me anyway:
I'm an expat in a non-English speaking country (relevant).
So I'm sitting in a bus on my way to the office the following conversation between two boys, neither of whom looked any older than 11 at most, occurs:
Boy 1 (in local tongue): somethingorother English class today ...
Boy 2 (in English - with a really thick accent): I'm arriving at 9 o'clock!
B1 (also English - even thicker accent): more like 9 o'cock [gestures in a way makes it abundantly clear he knows exactly what this means and stares directly at me]! 
B1 & B2: laugh, keep staring, luckily get off at the next stop
I'm not really sure what I find most horrible about this? Two kids clearly making crude remarks at a grown woman (albeit probably under the assumption that I'm local and don't get that sort of English), ESL kids even knowing that sort of English or feeling completely helpless at a situation which would have resulted in any grown man being threatened with instant castration.
So, AIBU or just getting a bit old?