I got the 3am phone call in San Fran from my ex-gf in Australia a few years ago. She was clueless about time zones, too, despite living in a country with 3 of them. Of course, everyone knows bad news doesn't wait until morning so it's the kind of thing to get your heart racing.
Meeting up is one thing, but what about people asking to you to bring stuff back, not realising you're trying to make the trip with just hand luggage and now have to take a long a suitcase full of crap they think is better in Europe:
Toblerone anyone? Don't people realise even Giant sells this? Some obscure brand of mustard you then have to spend hours looking for at the store Something a friend of your friend bought and wants you to take along. Probably large, heavy, and mostly glass or something fragile. Also, you need to meet up with this person, who has a hectic schedule, and doesn't live anywhere near you (but you do share a continent) Alcohol. If I'm bringing a bottle of alcohol to the states, it's only for me.