True Story:
[Me and my mate Jono were walking through a carpark. Jono was swearing loudly[
Me: Jono, stop it, this place is a public facility
Jono: Your MUM is a public facility!
I also did one to my English teacher on school camp. We were getting on the bus and she was telling us to put on our seatbelts.
Teacher: Ok everyone, click clack, front and back
Me: Your MUM takes it front and back!
ahh happy days :D