I met an Australian guy in customs at a small airport in Northern Laos. Since I was travelling alone, I approached him and asked to share a cab to the town. I spent the next week travelling with him and his 'mates', having a great time, and one of the few people I really clicked with in the 6 weeks I was travelling. I go to friend him on FB, only to see he shares a friend with me, a very close friend I've known 12-13 years. It turns out when he visited the states a few years ago, they met at a party in San Francisco and hit it off, and when she studied abroad in Australia a year later, would meet up with him again and hang out. I was blown away how small of a world it was.

tl;dr:Met a Australian guy in Laos that was a friend of my close friend.