Jokes for a long car ride

A car is a captive audience and a captive comedian. Somewhere around the second hour the games run out and the jokes begin, and the jokes have to be ones everyone in the car can tell and everyone can stand to hear twice. These are picked for the back seat: easy to remember, clean, and built on questions, so the person telling them can hold the answer hostage for a mile or two.

Take turns, keep score of the groans, and save the best one for the last stretch when morale is lowest.