I met two Russian people who were running a booth at a festival. One greeted me and tried to converse with me in English, but it soon became apparent that that wouldn't get us very far. So, we switched to Japanese, and made small talk for a few minutes before I made my purchase.

Not a huge deal overall, but I thought it was super cool to be able to make use of Japanese in a novel context. It was also interesting to meet someone where the best language for communication for both of us was an L2. As a native English speaker, that doesn't happen very often.