• Passport expiration date is OK?
• Flights all booked
• Hotel booked
• Rental car booked
• Get an international driver's permit
• Arrange a ride to the airport (examples below):
  • http://www.theairportshuttle.com/
  • http://www.supershuttle.com/en/BWIAirportShuttleBaltimore.html
• Make a copy of all your credit card information and leave at home (or with someone here)
• Copy your passport and carry it with you in your wallet
• Inform your credit companies of where you will be
• Lightweight your wallet (have a mugger's wallet)
• Hold your mail
• Arrange kid car seat situation (Rent with car or bring your own?)
• Thermostat set where you want it while you're away?
• What is your phone number where you will be staying (for all dates)?
• Neighbors know how to get a hold of you?
• Power adapters required? Do you have the right ones?
• Airline rules on bag restrictions (Air Greenland for instance is lighter than US)

Some items to think about:

• Do you want a SIM card for your travel phone?
• Drink container (mug)
• Some reading material (in a bag you can get to in flight)