Both of mine are offline and involve something in an everyday space that others wouldn't understand the significance of or possibly notice at all
First, the Hash House Harriers, the self-proclaimed "drinking club with a running problem". It's fun seeing chalk marks on pavement and knowing that a hash had recently passed by, even if it's been some time since I've been.
Second, geocaching. Tons and tons of containers hidden around you that you might never see if not actively looking for it. It's always a blast running into another person suspiciously looking about under a bench or whatever.
https://www.ibew.org/media-center/Articles/23Daily/2306/230620_IBEWandPaid
“We’re thankful that the Biden administration played the long game on sick days and stuck with us for months after Congress imposed our updated national agreement,” Russo said. “Without making a big show of it, Joe Biden and members of his administration in the Transportation and Labor departments have been working continuously to get guaranteed paid sick days for all railroad workers.