I have some domains with several extensions like .us, .net, .org etc. I want to use them all to redirect to one website, which is a social networking website. I want to use these domains in such a way that these domains become helpful in SEO point of view, this time. So far I am doing the followoing: pointing all domains to one directory on my hosting I have some other options including using 301 redirect, but I don't want to see duplicate contents in Google, What else do I need to do?