While Kurt and Tim were waiting for a podcast interviewee to log in recently, we decided to discuss the behavioral and psychological aspects of waiting. What do you do when you have unplanned time on your hands? Some people call it marginal time and others wasted time. But much of how we feel about slack in our schedule is dependent on how we frame it.
We reference Christopher Hsee's work on idleness to answer the question, "Why do we feel better taking back roads to avoid freeway traffic when we reach our destination at the same time?" Whether or not we know how long the wait is going to be didn't seem to make much difference to Kurt and Tim. We want to maximize its value in our lives. And although there is plenty of research on tolerable waiting times for different activities (longer for airport security lines, shorter for retail check-out lines, even shorter for web page refresh), we focused on what to do when the wait comes to us. 
We believe that being thoughtful about how the time gets used is the first and most important element to making the most of waiting. Using your deliberate (System 1) thinking to make a decision about how you're going to spend that time is the best thing you can do. Tim relates how he was stuck in the doctor's office recently and a person on the staff let him know the doctor was running "at least 20 minutes late." That was the trigger for the choice. What to do? Tim chose to meditate and was unsure how long the waiting went on because the meditation was so good.