I have an idea, some of us are traveling sometimes and cant host people. But the room is empty. We could give it for free, but as we are not enjoying the room, what about rent it for the days we travel to someone from couch surfing? so everybody will be happy. Those who have not found a host will find a room, cheaper that a hostel, and all the room for them, and the person that is traveling, could have that money to travel better, maybe he will find another room the same... so at the end will be like a circle. I say let use the empty rooms!! ;)