As a kid, bedtime is one of the ultimate constraints; being forced to go to bed right at an exact time every night feels like authoritarian oppression, almost symbolic of the limitations being imposed upon you. Of course, when you're seven years old, your bedtime is really for your own good, it's not really like you can be trusted to make your own decisions at that point for whether or not you're tired. But still, who among us didn't “cheat” our bedtimes, playing in our rooms long after our par…