Hi when I search on keywords the results being bought back are occasionally my IP address rather than my domain - what does this actually mean and how can I stop it happening? I was under the impression that IP and domain was one and the same thing? Therefore is what has happened purely a cosmetic thing (ie display url) or does Google think that it is another site and therefore am I in danger of dupe content problems?

I really am stumped with this one and appreciate any help!