I was biking from one class to another today. I had to stop at a stop sign, 'cause there were cars.
Problem 1: Brakes don't work. Solution: Turn (onto grass, not road) and stop with your feet. Having a freewheel which works dubiously at best may also help with the stopping. Come to a complete stop, which brings us to,
Problem 2: The handlebar stem detaches and falls off the bike. Solution: Jump clear, look around, wonder what's wrong with the people around you that they're not pointing and laughing at you, and come to the conclusion that maybe you need a new bike. (Then loosely put it back, carefully bike home to your sweet, sweet adjustable wrench and fix it.)