Welcome back from Wikimania 2017!
Well, I obviously met dozens of people, that's why we are meeting in person. The most memorable experience was probably when a colleague from my university walked into me in front of the venue. I hadn't even noticed that he had left Namibia to join his wife in Canada. His office used to be 50m from mine, and we bump into each other in Montreal! 10,000 miles from home! I explained to him how Wikipedia works---he wasn't attending the conference, just strolling through town.
I had a workshop which was approved via email, albeit not officially listed in the conference program: Pirates at work. Considering that there was the Editathon for Bassel Khartabil I felt it wasn't right to fish for attendees for my workshop, possibly reducing the amount of contributions to be made in his honour. I'm sure you see my point.