http://www.hospitalityclub.org/

Hospitality Club is the largest online hospitality exchange organization. You will meet friendly people and find free accommodation when you travel to any corner of the world. Membership is free and takes just a minute and everyone is welcome. Members can look at each other's profiles, send messages and post comments about their experience on the website...

http://www.couchsurfing.org/

CouchSurfing is a worldwide network for making connections between travelers and the local communities they visit...

http://www.roofswap.com/

RoofSwap provides you with a secure, easy to use and informative site to make your home swap or home rental a positive and memorable experience. ..

http://evergreenclub.com

With the Evergreen Club, you can experience delightful hospitality in members’ private homes for less price than the hotel. You can enjoy a restful stay in your host's guest room, a tasty breakfast, friendly conversation and sightseeing tips. ..