Windows Live Messenger itself already has that feature, as you said. Simply sign-in appear offline (or set your status to appear offline), right click the contact you wish to appear online to and choose "Appear online to this person." Repeat for any contact you wish to appear online to.
Why would you want a plugin (script) to do the same thing?
This post was edited on 10-19-2011 at 09:44 PM by Sunshine.
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