One thing I like to do and I am not really sure if this helps with SEO is to configure reverse dns on my dedicated web site IP address. By performing a reverse lookup and having it resolve to your web address I feel add a certain amout of credibility. If you are on a shared web hosting plan your site may be with hundred of other web sites on that same IP address.
To perform a reverse dns lookup go to dos or open a command prompt. Type nslookup and the numeric ip you want to check for reverse dns.