Whoever hosts is responsible for:

  1) adding event to the calendar, 
  2) posting to sudo-discuss mailing list and otherwise promoting,
  3) showing up!
  4) answering the door, giving tours, and otherwise being friendly and answering questions.
  5) have a planned activity ready to avoid awkwardness

You decide when to have it, but if it's on a weekday it should probably be no earlier than 6 pm.

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marc/juul