Greeting the interviewer
Keep your right hand warm but not sweaty, and shake the interviews hand with a well intentioned business handshake.
Often there will be more than one interviewer, try to get their business card or write down their name, so you will be able to address them by name when you answer their questions. It would also be a good idea to find out what the other participants' involvement is.
One group member spoke of an interview where he directed all of his answers to the outgoing employee, rather than the hiring manager. In another case, an interviewee didn't realize that a late arrival in the meeting was doing the technical evaluation of the candidate.