Sense of direction
When my college roommate got married, she sent the requisite "how to get here" sheet with the invitation. Since she was getting married in England, and most of her friends lived in the U.S., she felt compelled to include the following:
FROM AMERICA: Fly east over the Atlantic. Turn right at Iceland. Continue south, and get off the plane when you see red double-decker buses. If you see people drinking red wine, eating lots of cheese and inflaming world politics, you've gone too far.
Too far indeed.