This happened a while ago maybe a year to two ago but it is still great. Judy and I were out grocery shopping at one of the Walmart she worked at. We actually got in a line with a cashier she was friends with.
I started to "feel a rectal transmission" (fart) coming so I got out of line and walked a couple of aisles away and let it go. I thought I was pretty lucky because no one was in the aisle and it was a silent one. So there was no reason to feel any embarrassment. So I thought.
I got back into line by Judy and whispered what happened. By this time the smell followed me. It was really bad (and this is not the great part yet). We're standing there talking and all of a sudden the woman checking out ahead of us asked the cashier what the terrible smell was. She didn't know so they thought it might be some bad food so they started smelling everything. In the meantime I am standing back there laughing so hare I was crying. They never did figure out where the smell came from.