I haven't personally used either of these services but I do plan to in the future. I've heard mostly good things from BF members. Main thing to remember is to be considerate of your hosts.
http://www.warmshowers.org/
http://www.couchsurfing.org/
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2009 Bike Friday Season Tikit (commuting folder)
2007 Rivendell Atlantis (touring, general riding, errand runner, stuff hauler)
2007 IRO Mark V (SS)
2006 Rockhopper Comp Disc (Icebike)