If I'm in the mood for light conversation and if the other person is similarly in that mood, then why not? That doesn't happen all the time, but occasionally I've met some nice people and managed to learn something.

Memorable:

1. On a Paris-London flight I sat next to a British guy who was a lawyer, specializing in Customs issues. I learned a lot, it was interesting and fun.

2. On some flight into LAX, I got to talking to a guy who had been tasked with designing an Excel spreadsheet. I am very very good with Excel, so I gave him a few pointers. He was jotting then down on a napkin! ("Named ranges! Wow!" "Custom Functions! What will they think of next?!!")

3. My friend Don flew to London, one year, and got to talking with a chatty seatmate. When he got back to LA, he looked her up. Later, they married, had kids and stayed happily married until her death 40 years later.