 the couch cushions is this idea that when you do your January audit, you may actually discover that you had an amount left on an exchange you haven't used in a couple of years, and you thought it was only a couple hundred dollars, but because you forgot it for three years, it's now actually significantly more. I have had people write back to me and tell me that their couch contained college fund worth of coins in the cushions, and they were very, very happy to have followed that advice.