There is a "nerd filter" that people like me tend to pass through without realizing. On the other side of this filter, we are very likely to meet people we know, and in general people like us.
My most recent episode was at the 9000 foot visitor station on Mauna Kea. The folks there said that I shouldn't attempt to drive up to the telescopes without a 4-wheel-drive vehicle. So, I went in the parking lot and accosted occupants of the first 4-wheel-drive vehicle that came by. The driver of said vehicle had seen me lecture in San Francisco. I got my ride.
Just by standing at that 9000 foot visitor station, I'd passed through the nerd filter.
Then, a few weeks ago, I happened to come upon a local radio club's ham radio field day operation while hiking in the woods with my wife. An co-worker from 10 years ago walked up. It turned out he'd just gotten his ham license.
This stuff happens all of the time. Of course it helps that I am somewhat recognizable in tech circles, so people who know of me tend to walk up, but on the other hand I am not that well known.
What are your experiences beyond the nerd filter?