Q - R List of Web 2.0, Social Media, Networking, Tagging, Sharing Sites

http://www.quadriot.com/
http://www.quimble.com/
http://www.quintura.com/
http://www.rapleaf.com/
http://www.rawsugar.com/
http://www.rawsugar.com/index.faces
http://www.rdiculous.com/
http://www.recommendit.dehsoftware.com/
http://www.reddit.com/
http://www.rememberthemilk.com/
http://www.revish.com/
http://www.riffs.com/
http://www.riya.com/
http://www.rockyou.com/
http://www.rojo.com/
http://www.rollyo.com/
http://www.roundedcornr.com/
http://www.runfatboy.net/