It has been proven that the chances of meeting someone you know increases dramatically when you are with someone you don't want to be seen with.
Sign on a door:
"Push. If that doesn't work, Pull. If that doesn’t work, we’re closed."
Teach your kids about taxes...
Eat 30% of their ice cream.
I was flying between Toronto and Ottawa. It's only a 9 minute flight and so, to save money, I flew with a small airline in a little, twin-engine plane. About two minutes into the flight the pilot announced that we were going to have to turn back due to some engine trouble.
The nervous passenger I was seated next to turned to me and said, "If we lose an engine, how far do you think the other one will take us?"
I told him, "One engine? Oh, I'm sure it'll take us all the way to the scene of the crash. We'll probably make good time too. I bet we beat the paramedics there by at least a half hour."