I am familiar with the expression "couch potato" a person who spends a lot of time sitting on the couch watching TV, as if he or she were planted on the couch like a potato. But I have recently learned a new concept that is linked to the couch, only it's very different: "couch surfing."
In a way, couch surfing is just what it sounds like: traveling via the couch, easily, as if one were skimming across the waves of an ocean. Here's what happens in couch surfing: people who want to travel cheaply are connected with people who are willing to provide a place on their couch for the traveler to stay. Thus the traveler is "couch surfing."