For a second everything went quiet in the cab, then the driver said, "Look mister, don't ever do that again. You scared me half to death!"
The passenger apologized and said he didn't realize that a little tap could scare him so much.
The driver replied, "You're right. I'm sorry,really it's not your fault. Today is my first day as a cab driver. I've been driving a hearse for 25 years."