Long thread delves into piracy but the answer's there: "The computer name is easy: System Preferences -> Sharing -> Computer Name. Changing the name of the user is easy, too: System Preferences -> Accounts -> <choose your account> -> Name **
** Just note that the short user name of the first user made on the machine is virtually impossible to change - there is a long list on how to do is floating around, and it involves using the Terminal and NetInfo Manager, as far as I remember, but it's absolutely not recommended."

Nevada judge issues ill-defined ruling resulting in domain seizures Thx @stefanw

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